MAX6384XS33D7-T中文资料

October 2007Rev 11/17L6384EHigh-voltage half bridge driverFeatures■High voltage rail up to 600V■dV/dt immunity ±50V/nsec in full temperature range■Driver current capability:–400mA source,–650mA sink■Switching times 50/30 nsec rise/fall with 1nF load■CMOS/TTL Schmitt trigger inputs with hysteresis and pull down ■Shut down input ■Dead time setting ■Under voltage lock out ■Integrated bootstrap diode ■Clamping on V CC ■SO-8/DIP-8 packagesDescriptionThe L6384E is an high-voltage device, manufactured with the BCD"OFF-LINE"technology. It has an Half - Bridge Driver structure that enables to drive N-channel Power MOS or IGBT. The High Side (Floating) Section is enabled to work with voltage Rail up to 600V. The Logic Inputs are CMOS/TTL compatible for ease of interfacing with controlling devices. Matched delays between Low and High Side Section simplify high frequency operation. Dead time setting can be readily accomplished by means of an external resistor.Contents L6384EContents1Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.1Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.3Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.1AC operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.2DC operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.3Timing diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Bootstrap driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.1C BOOT selection and charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5Typical characteristic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 6Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 7Order codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162/17L6384E Electrical data3/171 Electrical data1.1Absolute maximum ratingsNote:ESD immunity for pins 6, 7 and 8 is guaranteed up to 900 V (Human Body Model)1.2 Thermal dataTable 1.Absolute maximum ratingsSymbol ParameterValue Unit V out Output voltage -3 to V boot -18 V V cc Supply voltage (1) 1.The device has an internal Clamping Zener between GND and the Vcc pin, It must not be supplied by aLow Impedence Voltage Source.- 0.3 to 14.6VI s Supply current (1) 25 mA V boot Floating supply voltage -1 to 618 V V hvg High side gate output voltage -1 to V boot V V lvg Low side gate output voltage -0.3 to V cc +0.3 V V i Logic input voltage-0.3 to V cc +0.3 V V sd Shut down/dead time voltage -0.3 to V cc +0.3V dV out /d t Allowed output slew rate50 V/ns P tot T otal power dissipation (T j = 85 °C) 750 mW T J Junction temperature 150 °C T sStorage temperature-50 to 150°CTable 2.Thermal dataSymbol Parameter SO-8 DIP-8Unit R th(JA)Thermal Resistance Junction to ambient150100°C/WElectrical data L6384E4/171.3 Recommended operating conditionsTable 3.Recommended operating conditionsSymbol Pin ParameterTest conditionMinTyp Max UnitV out 6 Output Voltage (1)1.If the condition Vboot - Vout < 18V is guaranteed, Vout can range from -3 to 580V.580 V V BS (2)2.V BS = V boot - V out8Floating Supply Voltage (1)17 V f sw Switching Frequency HVG,LVG load C L = 1nF400 kHz V cc2 Supply VoltageV clampV T jJunction Temperature-45 125°CL6384E Pin connection5/172 Pin connectionTable 4.Pin descriptionN°PinTypeFunction1 IN ILogic Input: it is in phase with HVG and in opposition of phase with LVG. Itis compatible to V CC voltage. [V il Max = 1.5V , V ih Min = 3.6V] 2 V ccSupply input voltage: there is an internal clamp [Typ. 15.6V]3 DT/SD I High impedance pin with two functionalities. When pulled lower than V dt [T yp. 0.5V] the device is shut down. A voltage higher than V dt sets the dead time between high side gate driver and low side gate driver. The dead time value can be set forcing a certain voltage level on the pin or connecting a resistor between pin 3 and ground. Care must be taken toavoid below threshold spikes on pin 3 that can cause undesired shut downof the IC. For this reason the connection of the components between pin 3 and ground has to be as short as possible. This pin can not be left floating for the same reason. The pin has not be pulled through a low impedance to V CC , because of the drop on the current source that feeds R dt . The operative range is: V dt ....270K ⋅ I dt , that allows a dt range of 0.4 - 3.1µs. 4 GNDGround5 LVG OLow Side Driver Output: the output stage can deliver 400mA source and 650mA sink [Typ. Values]. The circuit guarantees 0.3V max on the pin (@ I sink = 10mA) with V CC > 3V and lower than the turn on threshold. Thisallows to omit the bleeder resistor connected between the gate and the source of the external mosfet normally used to hold the pin low; the gate driver ensures low impedance also in SD conditions. 6 V out OHigh Side Driver Floating Reference: layout care has to be taken to avoidbelow ground spikes on this pin. 7 HVG O High Side Driver Output: the output stage can deliver 400mA source and 650mA sink [Typ. Values]. The circuit gurantees 0.3V max between this pin and V out(@ I sink = 10mA) with V CC > 3V and lower than the turn onthreshold. This allows to omit the bleeder resistor connected between the gate and the source of the external mosfet normally used to hold the pin low; the gate driver ensures low impedance also in SD conditions.8 VbootBootstrap Supply Voltage: it is the high side driver floating supply. The bootstrap capacitor connected between this pin and pin 6 can be fed by an internal structure named "bootstrap driver" (a patented structure). This structure can replace the external bootstrap diode.6/173 Electrical characteristics3.1 AC operation3.2 DC operationTable 5.AC operation electrical characteristcs (V CC = 14.4V; T J = 25°C)Symbol PinParameterTest conditionMinTyp MaxUnit t on 1 vs 5,7 High/low side driver turn-onpropagation delayV out = 0V R dt = 47k Ω200+dtnst onsd3 vs 5,7 Shut down input propagation delay220 280 nst off1 vs 5,7 High/low side driver turn-offpropagation delayV out = 0V R dt = 47k Ω 250300 ns V out = 0V R dt = 146k Ω 200 250 nsV out = 0V R dt = 270k Ω 170 200 ns t r 5,7Rise timeC L = 1000pF 50 ns t f5,7 F all timeC L = 1000pF30nsTable 6.DC operation electrical characteristcs (V CC = 14.4V; T J = 25°C)SymbolPinParameterTest conditionMinTypMaxUnitSupply voltage section V clamp 2Supply voltage clampingI s = 5mA14.6 15.6 16.6 V V ccth1 2 V CC UV turn on threshold11.51212.5VV ccth2 2 V CC UV turn off threshold 9.5 10 10.5 V V cchys V CC UV Hysteresis 2 V I qccu Undervoltage quiescentsupply current V cc ≤ 11V 150 µA I qccQuiescent currentV in = 0380500µABootstrapped supply voltage section V boot 8Bootstrap supply voltage 17 V I QBS Quiescent currentIN = HIGH200 µA I LK High voltage leakage current V hvg = V out = V boot = 600V10µA R dsonBootstrap driver on resistance (1)V cc ≥12.5V; IN = LOW125Ω7/173.3 Timing diagramSymbolPinParameterTest conditionMinTypMaxUnitHigh/Low side driver I so 5,7Source short circuit current V IN = V ih (t p < 10µs) 300 400 mA I siSink short circuit currentV IN = V il (tp < 10µs) 500 650mALogic inputs V il 1,3 Low level logic thresholdvoltage1.5 VV ih High level logic threshold voltage3.6 VI ih High level logic input current V IN = 15V 5070 µA I il Low level logic input current V IN = 0V 1µA I ref 3Dead time setting current28µA dt 3 vs5,7Dead time setting range (2) R dt = 47k ΩR dt = 146k ΩR dt = 270k Ω0.4 0.51.52.73.1µs µs µs V dt3 Shutdown threshold0.5V1.R DS(on) is tested in the following way:where I 1 is pin 8 current when V CBOOT = V CBOOT1, I 2 when V CBOOT = V CBOOT22.Pin 3 is a high impedence pin. Therefore dt can be set also forcing a certain voltage V 3 on this pin. Thedead time is the same obtained with a R dt if it is: R dt × I ref = V 3.Table 6.DC operation electrical characteristcs (continued)(V CC = 14.4V; T J = 25°C)R DSON V CCV CBOOT1–()V CC V CBOOT2–()–I 1V CC ,V CBOOT1()I 2V CC ,V CBOOT2()–------------------------------------------------------------------------------------------------------=Bootstrap driver L6384E8/174 Bootstrap driverA bootstrap circuitry is needed to supply the high voltage section. This function is normallyaccomplished by a high voltage fast recovery diode (Figure 4 a). In the L6384E a patented integrated structure replaces the external diode. It is realized by a high voltage DMOS, driven synchronously with the low side driver (LVG), with in series a diode, as shown in Figure 4 b. An internal charge pump (Figure 4 b) provides the DMOS driving voltage. The diode connected in series to the DMOS has been added to avoid undesirable turn on of it.4.1 C BOOT selection and chargingTo choose the proper C BOOT value the external MOS can be seen as an equivalent capacitor. This capacitor C EXT is related to the MOS total gate charge:The ratio between the capacitors C EXT and C BOOT is proportional to the cyclical voltage loss.It has to be:C BOOT >>>C EXTe.g.: if Q gate is 30nC and V gate is 10V , C EXT is 3nF . With C BOOT = 100nF the drop would be 300mV.If HVG has to be supplied for a long time, the C BOOT selection has to take into account also the leakage losses.e.g.: HVG steady state consumption is lower than 200µA, so if HVG T ON is 5ms, C BOOT has to supply 1µC to C EXT . This charge on a 1µF capacitor means a voltage drop of 1V .The internal bootstrap driver gives great advantages: the external fast recovery diode can be avoided (it usually has great leakage current).This structure can work only if V OUT is close to GND (or lower) and in the meanwhile the LVG is on. The charging time (T charge ) of the C BOOT is the time in which both conditions are fulfilled and it has to be long enough to charge the capacitor.The bootstrap driver introduces a voltage drop due to the DMOS R DSON (typical value: 125 Ω). At low frequency this drop can be neglected. Anyway increasing the frequency it must be taken in to account.The following equation is useful to compute the drop on the bootstrap DMOS:where Q gate is the gate charge of the external power MOS, R dson is the on resistance of thebootstrap DMOS, and T charge is the charging time of the bootstrap capacitor.C EXT Qgate V gate--------------=V drop I ch e arg R dson V drop →Q gateT ch e arg -------------------R dson==L6384E Bootstrap driver9/17For example: using a power MOS with a total gate charge of 30nC the drop on the bootstrap DMOS is about 1V , if the T charge is 5µs. In fact:V drop has to be taken into account when the voltage drop on C BOOT is calculated: if this drop is too high, or the circuit topology doesn’t allow a sufficient charging time, an external diode can be used.V drop 30nC5µs--------------125Ω0.8V∼⋅=Typical characteristic L6384E10/175 Typical characteristicFigure 5.Typical rise and fall times vsFigure 6.Quiescent current vs supply Figure 7.Dead time vs resistance Figure 8.Driver propagation delay vsFigure 9.Dead time vs temperatureFigure 10.Shutdown threshold vs分销商库存信息:STML6384ED013TR L6384E L6384ED。

General DescriptionThe MAX6381–MAX6390 microprocessor (µP) supervisory circuits monitor power supply voltages from +1.8V to +5.0V while consuming only 3µA of supply current at +1.8V. Whenever V CC falls below the factory-set reset thresholds, the reset output asserts and remains assert-ed for a minimum reset timeout period after V CC rises above the reset threshold. Reset thresholds are available from +1.58V to +4.63V, in approximately 100mV incre-ments. Seven minimum reset timeout delays ranging from 1ms to 1200ms are available.The MAX6381/MAX6384/MAX6387 have a push-pull active-low reset output. The MAX6382/MAX6385/MAX6388 have a push-pull active-high reset output,and the MAX6383/MAX6386/MAX6389/MAX6390 have an open-drain active-low reset output. The MAX6384/MAX6385/MAX6386 also feature a debounced manual reset input (with internal pullup resistor). The MAX6387/MAX6388/MAX6389 have an auxiliary input for monitoring a second voltage. The MAX6390 offers a manual reset input with a longer V CC reset timeout period (1120ms or 1200ms) and a shorter manual reset timeout (140ms or 150ms).The MAX6381/MAX6382/MAX6383 are available in 3-pin SC70 packages and the MAX6384–MAX6390 are avail-able in 4-pin SC70 packages.________________________ApplicationsComputers ControllersIntelligent InstrumentsCritical µP and µC Power Monitoring Portable/Battery-Powered Equipment Dual Voltage SystemsFeatureso Factory-Set Reset Threshold Voltages Ranging from +1.58V to +4.63V in Approximately 100mV Increments o ±2.5% Reset Threshold Accuracy Over Temperature (-40°C to +125°C)o Seven Reset Timeout Periods Available: 1ms,20ms, 140ms, 280ms, 560ms, 1120ms, 1200ms (min)o 3 Reset Output OptionsActive-Low Push-Pull Active-High Push-Pull Active-Low Open-Draino Reset Output State Guaranteed Valid Down to V CC = 1Vo Manual Reset Input (MAX6384/MAX6385/MAX6386)o Auxiliary RESET IN(MAX6387/MAX6388/MAX6389)o V CC Reset Timeout (1120ms or 1200ms)/Manual Reset Timeout (140ms or 150ms) (MAX6390)o Negative-Going V CC Transient Immunity o Low Power Consumption of 6µA at +3.6V and 3µA at +1.8V o Pin Compatible withMAX809/MAX810/MAX803/MAX6326/MAX6327/MAX6328/MAX6346/MAX6347/MAX6348, and MAX6711/MAX6712/MAX6713o Tiny 3-Pin SC70 and 4-Pin SC70 PackagesMAX6381–MAX6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits________________________________________________________________Maxim Integrated Products1Pin Configurations19-1839; Rev 1; 04/01Ordering InformationOrdering Information continued at end of data sheet.Typical Operating Circuit appears at end of data sheet.Selector Guide appears at end of data sheet.Note:Insert reset threshold suffix (see Reset Threshold table)after "XR" or "XS". Insert reset timeout delay (see Reset Timeout Delay table) after "D" to complete the part number. Sample stock is generally held on standard versions only (seeStandard Versions table). Standard versions have an order increment requirement of 2500 pieces. Nonstandard versions have an order increment requirement of 10,000 pieces.Contact factory for availability of nonstandard versions.*MAX6390 is available with D4 or D7 timing only.For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .M A X 6381–M A X 6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC to GND..........................................................-0.3V to +6.0V RESET Open-Drain Output....................................-0.3V to +6.0V RESET , RESET (Push-Pull Output).............-0.3V to (V CC + 0.3V)MR , RESET IN.............................................-0.3V to (V CC + 0.3V)Input Current (V CC ).............................................................20mA Output Current (All Pins).....................................................20mAContinuous Power Dissipation (T A = +70°C)3-Pin SC70 (derate 2.9mW/°C above +70°C)........235mW 4-Pin SC70 (derate 3.1mW/°C above +70°C)........245mW Operating Temperature Range .........................-40°C to +125°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX6381–MAX6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits_______________________________________________________________________________________3M A X 6381–M A X 6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 4______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)215436789-40-105-25203550658095110125SUPPLY CURRENT vs. TEMPERATURE(NO LOAD)TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )25292735333137394143-40-105-25203550658095110125POWER-DOWN RESET DELAYvs. TEMPERATURETEMPERATURE (°C)P O W E R -D O W N R E S E T D E L A Y (µs )0.940.980.961.021.001.061.041.08-40-10520-253550658095110125NORMALIZED POWER-UP RESET TIMEOUTvs. TEMPERATUREM A X 6381/90 t o c 03TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T P E R I O D0.9900.9851.0150.9950.9901.0001.0051.0101.020-40-10520-253550958011065125M A X 6381/90 t o c 04TEMPERATURE (°C)N O R M A L I Z E D R E S E TT H R E S H O L D NORMALIZED RESET THRESHOLDvs. TEMPERATURE00.40.20.80.61.01.2063912OUTPUT VOLTAGE LOW vs. SINK CURRENTI SINK (mA)V O L (V )01.00.52.01.52.53.00500750250100012501500OUTPUT VOLTAGE HIGH vs. SOURCE CURRENTI SOURCE (µA)V O H (V )45001100010010MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE15050350250500200100400300RESET COMPARATOR OVERDRIVE, V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )3.53.93.74.54.34.14.74.95.35.15.5-40-105-25203550658095110125RESET IN TO RESET DELAYvs. TEMPERATUREM A X 6381/90 t o c 08TEMPERATURE (°C)R E S E T I N D E L A Y (µs )MAX6381–MAX6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits_______________________________________________________________________________________5M A X 6381–M A X 6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 6_______________________________________________________________________________________Detailed DescriptionRESET OutputA µP reset input starts the µP in a known state. These µP supervisory circuits assert reset to prevent code execution errors during power-up, power-down, or brownout conditions.Reset asserts when V CC is below the reset threshold;once V CC exceeds the reset threshold, an internal timer keeps the reset output asserted for the reset timeout period. After this interval, reset output deasserts. Reset output is guaranteed to be in the correct logic state for V CC ≥1V.Manual Reset Input (MAX6384/MAX6385/MAX6386/MAX6390)Many µP-based products require manual reset capabil-ity, allowing the operator, a test technician, or external logic circuitry to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low,and for the reset active timeout period (t RP ) after MR returns high. This input has an internal 63k Ωpullup resistor (1.35k Ωfor MAX6390), so it can be left uncon-nected if it is not used. MR can be driven with TTL or CMOS logic levels, or with open-drain/collector outputs.Connect a normally open momentary switch from MR to G ND to create a manual-reset function; external debounce circuitry is not required. If MR is driven from long cables or if the device is used in a noisy environ-ment, connecting a 0.1µF capacitor from MR to G ND provides additional noise immunity.RESET IN Comparator(MAX6387/MAX6388/MAX6389)RESET IN is compared to an internal +1.27V reference.If the voltage at RESET IN is less than 1.27V, reset asserts. Use the RESET IN comparator as a user-adjustable reset detector or as a secondary power-sup-ply monitor by implementing a resistor-divider at RESET IN (shown in Figure 1). Reset asserts when either V CC or RESET IN falls below its respective threshold volt-age. Use the following equation to set the threshold:V INTH = V THRST (R1/R2 + 1)where V THRST = +1.27V. To simplify the resistor selec-tion, choose a value of R2 and calculate R1:R1 = R2 [(V INTH /V THRST ) - 1]Since the input current at RESET IN is 50nA (max),large values can be used for R2 with no significant loss in accuracy.___________Applications InformationNegative-Going V CC TransientsIn addition to issuing a reset to the µP during power-up,power-down, and brownout conditions, the MAX6381–MAX6390 are relatively immune to short dura-tion negative-going V CC transients (glitches).The Typical Operating Characteristics section shows the Maximum Transient Durations vs. Reset Comparator Overdrive, for which the MAX6381–MAX6390 do not generate a reset pulse. This graph was generated usinga negative-going pulse applied to V CC , starting above the actual reset threshold and ending below it by the magni-tude indicated (reset comparator overdrive). The graph indicates the typical maximum pulse width a negative-going V CC transient may have without causing a reset pulse to be issued. As the magnitude of the transient increases (goes farther below the reset threshold), the maximum allowable pulse width decreases. A 0.1µF capacitor mounted as close as possible to V CC provides additional transient immunity.Ensuring a Valid RESET Output Down to V CC = 0The MAX6381–MAX6390 are guaranteed to operate properly down to V CC = 1V. In applications that require valid reset levels down to V CC = 0, a pulldown resistor to active-low outputs (push/pull only, Figure 2) and a pullup resistor to active-high outputs (push/pull only) will ensure that the reset line is valid while the reset output can no longer sink or source current. This scheme doesnot work with the open-drain outputs of the MAX6383/MAX6386/MAX6389/MAX6390. The resistor value used is not critical, but it must be small enough not to load the reset output when V CC is above the reset threshold. For most applications, 100k Ωis adequate.MAX6381–MAX6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits_______________________________________________________________________________________7M A X 6381–M A X 6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 8Selector GuideChip InformationTRANSISTOR COUNT: 647PROCESS: BiCMOS*MR is for MAX6384/MAX6385/MAX6386/MAX6390**RESET IN is for MAX6387/MAX6388/MAX6389( ) are for MAX6382/MAX6385/MAX6388Pin Configurations (continued)MAX6381–MAX6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits_______________________________________________________________________________________9Ordering Information(continued)Note:Insert reset threshold suffix (see Reset Threshold table)after "XR" or "XS". Insert reset timeout delay (see Reset Timeout Delay table) after "D" to complete the part number. Sample stock is generally held on standard versions only (seeStandard Versions table). Standard versions have an order increment requirement of 2500 pieces. Nonstandard versions have an order increment requirement of 10,000 pieces.Contact factory for availability of nonstandard versions.*MAX6390 is available with D4 or D7 timing only.M A X 6381–M A X 6390SC70, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 10______________________________________________________________________________________Package InformationSC70, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsMaxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600____________________11©2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.MAX6381–MAX6390Package Information (continued)元器件交易网。

ADM6384YKS29D3Z-R7ADM6384YKS23D3Z-R7Microprocessor SupervisoryRev. CInformation furnished by Analog Devices is believed to be accurate and reliable. However, noresponsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. T rademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, M A 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.461.3113 ©2005–2011 Analog Devices, Inc. All rights reserved.FEATURESPrecision power supply monitoring31 reset threshold options: 1.58 V to 5.0 VFour reset timeouts: 1 ms, 20 ms, 140 ms, and 1120 ms Manual reset inputReset output stagePush-pull active-lowGuaranteed reset output valid to V CC = 1 VPower supply glitch immunitySpecified over the −40°C to +125°C temperature range4-lead SC70 packageAPPLICATIONSMicroprocessor systemsComputersControllersIntelligent instrumentsPortable equipmentGENERAL DESCRIPTIONThe ADM6384 is a supervisory circuit that monitors power supply voltage levels in microprocessor-based systems. A power-on reset signal is generated when the supply voltage rises to a preset threshold level. The debounced manual reset input of the ADM6384 can be used to initiate a reset by means of an external push button or logic signal.The part is available in a choice of 31 reset threshold options, from 1.58 V to 5.0 V. The minimum reset timeout periods are 1 ms, 20 ms, 140 ms, and 1120 ms.The ADM6384 is available in a 4-lead SC70 package and typi-cally consumes only 7 µA, making it suitable for use in low power, portable applications. FUNCTIONAL BLOCK DIAGRAMSFigure 1.535-2Figure 2.ADM6384Rev. C | Page 2 of 12TABLE OF CONTENTSFeatures .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagrams ............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Absolute Maximum Ratings ............................................................ 5 ESD Caution .................................................................................. 5 Pin Configuration and Function Descriptions ............................. 6 Typical Performance Characteristics ..............................................7 Circuit Description............................................................................9 Reset Output ..................................................................................9 Manual Reset Input .......................................................................9 Applications Information .............................................................. 10 Negative-Going V CC Transients ................................................ 10 Ensuring Reset Valid to V CC = 0 V ........................................... 10 Outline Dimensions ....................................................................... 11 Ordering Guide .. (11)REVISION HISTORY4/11—Rev. B to Rev. CUpdated Outline Dimensions ....................................................... 11 Changes to Ordering Guide . (11)7/08—Rev. A to Rev. BChanges to Figure 5, Figure 8, and Figure 9.................................. 7 Changes to Figure 10 ........................................................................ 8 Changes to Figure 15 ...................................................................... 11 Changes to Ordering Guide . (11)1/07—Rev. 0 to Rev. AUpdated Format .................................................................. U niversal Changes to Specifications Table ...................................................... 3 Updated Outline Dimensions ....................................................... 11 Changes to Ordering Guide . (11)7/05—Revision 0: Initial VersionSPECIFICATIONSV CC = full operating range, T A = −40°C to +125°C, unless otherwise noted.Rev. C | Page 3 of 121 T A = 25°C only.Rev. C | Page 4 of 12Rev. C | Page 5 of 12ABSOLUTE MAXIMUM RATINGST A = 25°C, unless otherwise noted.Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operationalsection of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Rev. C | Page 6 of 12PIN CONFIGURATION AND FUNCTION DESCRIPTIONSGNDRESET 05305-003Figure 3. Pin ConfigurationRev. C | Page 7 of 12TYPICAL PERFORMANCE CHARACTERISTICS05305-004TEMPERATURE (°C)120–40–2020406080100I C C (µA )10.09.57.57.06.59.08.58.06.05.55.04.54.03.5 Figure4. Supply Current vs. Temperature05305-005TEMPERATURE (°C)120–40–2040201008060N O R M A L I Z E D R E S E T T I M E O U T (m s )1.201.151.101.050.951.000.900.850.80Figure 5. Normalized Reset Timeout Period vs. Temperature05305-006TEMPERATURE (°C)120–40–2040201008060V C C T O R E S E T O U T P U T D E L A Y (µs )100908060704050201030Figure 6. V CC to Reset Output Delay vs. Temperature05305-007TEMPERATURE (°C)120–40–2040201008060N O R M A L I Z E D R E S E T T H R E S H O L D (V )1.051.031.041.011.020.991.000.970.980.950.96Figure 7. Normalized Reset Threshold vs. Temperature05305-008I SINK (mA)70123456V OL (V )0.200.150.100.05Figure 8. Output Voltage Low vs. I SINK05305-009I SOURCE (mA)1.000.20.40.60.8V O H (V )2.922.902.882.862.842.82Figure 9. Output Voltage High vs. I SOURCERev. C | Page 8 of 1205305-010OVERDRIVE V OD (mV)100010100M A X I M U M V C C T R A N S I E N T D U R A T I O N (µs )160120140100608040200Figure 10. Maximum V CC Transient Duration vs. Reset Threshold Overdrive05305-011TEMPERATURE (°C)–40–2020406080100120M A N U A L R E S E T T O R E S E T D E L A Y (n s )340280320300260220240200180160140120100Figure 11. Manual Reset Minimum Pulse Width vs. TemperatureRev. C | Page 9 of 12CIRCUIT DESCRIPTIONThe ADM6384 provides microprocessor supply voltage supervi-sion by controlling the microprocessor reset input. Code execution errors are avoided during power-up, power-down, and brownout conditions by asserting a reset signal when the supply voltage is below a preset threshold. In addition, the ADM6384 allows supply voltage stabilization with a fixed timeout before the reset deasserts after the supply voltage rises above the threshold. If the user detects a problem with the system operation, a manual reset input is available to reset the microprocessor by means of an external push-button, for example.RESET OUTPUTThe ADM6384 features an active-low, push-pull reset output. The reset signal is guaranteed to be logic low for V CC down to 1 V . The reset output is asserted when V CC is below the reset threshold (V TH ) or when MR is driven low. Reset remains asserted for the duration of the reset active timeout period (t RP ) after V CC rises above the reset threshold or after MR transitions from low to high. Figure 12 illustrates the behavior of the reset outputs. VV V CC RESET05305-012Figure 12. Reset Timing DiagramMANUAL RESET INPUTThe ADM6384 features a manual reset input (MR ) that, when driven low, asserts the reset output. When MR transitions from low to high, reset remains asserted for the duration of the reset active timeout period before deasserting. The MR input has a 52 kΩ internal pull-up so that the input is always high when unconnected. An external push-button switch can be connected between MR and ground so that the user can generate a reset. Debounce circuitry for this purpose is integrated on-chip. Noise immunity is provided on the MR input, and fast, negative-going transients of up to 100 ns (typical) are ignored. A 0.1 µF capacitor between MR and ground provides additional noise immunity.Rev. C | Page 10 of 12APPLICATIONS INFORMATIONNEGATIVE-GOING V CC TRANSIENTSTo avoid unnecessary resets caused by fast power supply tran-sients, the ADM6384 is equipped with glitch rejection circuitry. The typical performance characteristic shown in Figure 10 plots V CC transient duration vs. the transient magnitude. The curves show combinations of transient magnitude and duration for which a reset is not generated for 4.63 V and 2.93 V reset threshold parts. For example, with the 2.93 V threshold, a transient that goes 100 mV below the threshold and lasts 8 µs typically does not cause a reset, but if the transient is any greater in magnitude or duration, a reset is generated. An optional 0.1 µF bypass capacitor mounted close to V CC provides additional glitch rejection.ENSURING RESET VALID TO V CC = 0 VBoth active-low and active-high reset outputs are guaranteed to be valid for V CC as low as 1 V . However, by using an external resistor with push-pull configured reset outputs, valid outputs for V CC as low as 0 V are possible. For an active-low reset out-put, a resistor connected between RESET and ground pulls the output low when it is unable to sink current. A large resistance such as 100 kΩ should be used to avoid overloading the reset output when V CC is above 1 V .Figure 13. Ensuring Reset Valid to V CC = 0 VADM6384Rev. C | Page 11 of 12OUTLINE DIMENSIONS*PACKAGE OUTLINE CORRESPONDS IN FULL TO EIAJ SC82EXCEPT FOR WIDTH OF PIN 2AS SHOWN.072809-A0.100.10Figure 14. 4-Lead Thin Shrink Small Outline Transistor Package [SC70](KS-4)Dimensions shown in millimeters1: 1ms (MIN)2: 20ms (MIN)3: 140ms (MIN)4:1120ms (MIN)Y: –40°C (16TO 50)05305-014Figure 15. Ordering Code StructureORDERING GUIDEStandard Models 1, 2ResetThreshold (V) ResetTimeout (ms) Temperature RangeQuantity Package Description PackageOption BrandingADM6384YKS23D3Z-R7 2.31 140 −40°C to +125°C 3k 4-Lead SC70 KS-4 N0R ADM6384YKS26D3Z-R7 2.63 140 −40°C to +125°C 3k 4-Le a d SC70 KS-4 N0R ADM6384YKS29D1Z-R7 2.93 1 −40°C to +125°C 3k 4-Lead SC70 KS-4 N0R ADM6384YKS29D3Z-R7 2.93 140 −40°C to +125°C 3k 4-Lead SC70 KS-4 N0R ADM6384YKS31D1Z-R7 3.08 1 −40°C to +125°C 3k 4-Lead SC70 KS-4 N0R ADM6384YKS31D2Z-R7 3.08 20 −40°C to +125°C 3k 4-Le a d SC70 KS-4 N0R ADM6384YKS34D2Z-R7 3.4 20 −40°C to +125°C 3k 4-Le a d SC70 KS-4 N0R ADM6384YKS39D2Z-R7 3.9 20 −40°C to +125°C 3k 4-Le a d SC70 KS-4 N0R ADM6384YKS45D3Z-R7 4.5 140 −40°C to +125°C 3k 4-Le a d SC70 KS-4 N0R ADM6384YKS46D2Z-R74.63 20 −40°C to +125°C 3k 4-Le a d SC70 KS-4 N0R1If ordering nonstandard models, complete the ordering code shown in Figure 15 by inserting reset timeout and reset threshold suffixes. Contact sales for availability of nonstandard models. 2Z = RoHS Compliant Part.ADM6384Rev. C | Page 12 of 12NOTES©2005–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners.D05305-0-4/11(C)ADM6384YKS29D3Z-R7ADM6384YKS23D3Z-R7。

UC3843中文资料简介UC3843是一种高性能固定频率电流模式PWM控制器。

它是专为开关电源和DC-DC转换器设计的，可提供快速且精确的响应。

UC3843在广泛的电源和应用中得到了广泛的应用，具有可靠性高、性能优越等特点。

本文档将详细介绍UC3843的特性、应用领域、电路原理和参数规格等相关信息。

特性1.工作电压范围：8V - 35V2.最大输出频率：500kHz3.可调或固定输出电压4.可调或固定输出电流5.内部电流检测和保护功能6.过温度保护7.低功耗待机模式应用领域UC3843广泛应用于以下领域：1.开关电源2.DC-DC转换器3.逆变器4.电池充电器5.照明系统6.电动机驱动器电路原理UC3843采用了固定频率PWM控制方式，通过周期性的开关MOSFET来控制电源输出。

其基本电路原理如下：UC3843基本电路原理图•Vin为输入电源电压，通常为DC电压•Vref为参考电压，可以通过外部电路调整来控制输出电压或电流•COMP为比较器输入引脚，用于比较反馈信号和参考电压的大小•PWM为PWM信号输出引脚，用于控制开关MOSFET的开关状态•Feedback为反馈信号输入引脚，用于监测输出电压或电流UC3843通过不断比较反馈信号和参考电压的大小，动态调整PWM信号的占空比，以达到稳定输出的目的。

同时，UC3843还具有内部电流检测和保护功能，可以保护电源和负载免受过电流的影响。

参数规格UC3843的主要参数规格如下：参数典型值工作电压范围8V - 35V输出频率范围100kHz - 500kHz输出电压范围0V - 30V输出电流范围0A - 3A参考电压 2.5V最大工作温度125°C待机模式静态功耗（最大）5mA使用注意事项在使用UC3843时，应注意以下事项：1.请严格按照UC3843的电气参数和工作条件进行设计和使用，避免超过其额定数值范围。

2.请注意电路的散热和绝缘设计，确保电路稳定、安全。

General DescriptionThe MAX6369–MAX6374 are pin-selectable watchdog timers that supervise microprocessor (µP) activity and signal when a system is operating improperly. During normal operation, the microprocessor should repeated-ly toggle the watchdog input (WDI) before the selected watchdog timeout period elapses to demonstrate that the system is processing code properly. If the µP does not provide a valid watchdog input transition before the timeout period expires, the supervisor asserts a watch-dog (WDO ) output to signal that the system is not exe-cuting the desired instructions within the expected time frame. The watchdog output pulse can be used to reset the µP or interrupt the system to warn of processing errors.The MAX6369–MAX6374 are flexible watchdog timer supervisors that can increase system reliability through notification of code execution errors. The family offers several pin-selectable watchdog timing options to match a wide range of system timing applications:•Watchdog startup delay: provides an initial delay before the watchdog timer is started.•Watchdog timeout period: normal operating watch-dog timeout period after the initial startup delay.•Watchdog output/timing options: open drain (100ms)or push-pull (1ms).The MAX6369–MAX6374 operate over a +2.5V to +5.5V supply range and are available in miniature 8-pin SOT23 packages.________________________ApplicationsEmbedded Control Systems Industrial ControllersCritical µP and Microcontroller (µC) Monitoring AutomotiveTelecommunications NetworkingFeatures♦Precision Watchdog Timer for Critical µP Applications ♦Pin-Selectable Watchdog Timeout Periods ♦Pin-Selectable Watchdog Startup Delay Periods ♦Ability to Change Watchdog Timing Characteristics Without Power Cycling ♦Open-Drain or Push-Pull Pulsed Active-Low Watchdog Output ♦Watchdog Timer Disable Feature ♦+2.5V to +5.5V Operating Voltage ♦8µA Low Supply Current♦No External Components Required ♦Miniature 8-Pin SOT23 PackageMAX6369–MAX6374Pin-Selectable Watchdog Timers19-1676; Rev 3; 11/05Ordering InformationPin Configuration appears at end of data sheet.Note:All devices are available in tape-and-reel only. Required order increment is 2,500 pieces.Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing “-T” with “+T” when ordering.Selector GuideFor pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at1-888-629-4642, or visit Maxim’s website at .M A X 6369–M A X 6374Pin-Selectable Watchdog Timers 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +2.5V to +5.5V, SET_ = V CC or GND, T A = -40°C to +85°C, unless otherwise noted. Typical values are at T A = +25°C andStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Terminal Voltage (with respect to GND)V CC .....................................................................-0.3V to +6V WDI.....................................................................-0.3V to +6V WDO (Open Drain: MAX6369/71/73).................-0.3V to +6V WDO (Push-Pull: MAX6370/72/74 .......-0.3V to (V CC + 0.3V)SET0, SET1, SET2................................-0.3V to (V CC + 0.3V)Maximum Current, Any Pin (input/output)...........................20mAContinuous Power Dissipation (T A = +70°C)SOT23-8 (derate 8.75mW/°C above +70°C)...............700mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Junction Temperature......................................................+150°C Lead Temperature (soldering, 10s).................................+300°C V CC Rise or Fall Rate......................................................0.05V/µsMAX6369–MAX6374Pin-Selectable Watchdog Timers_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)M A X 6369–M A X 6374Pin-Selectable Watchdog Timers 4_______________________________________________________________________________________461081214-4010-15356085SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )Typical Operating Characteristics(Circuit of Figure 1, T A = +25°C, unless otherwise noted .)0.9970.9990.9981.0011.0001.0021.003-4010-15356085WATCHDOG TIMEOUT PERIODvs. TEMPERATUREM A X 6369/74-02TEMPERATURE (°C)N O R M A L I Z E D W A T C H D O G T I M E O U T P E R I O DELECTRICAL CHARACTERISTICS (continued)Note 2:Guaranteed by design.Note 3:In this setting the watchdog timer is inactive and startup delay ends when WDI sees its first level transition. See SelectingDevice Timing for more information.Note 4:After power-up, or a setting change, there is an internal setup time during which WDI is ignored.MAX6369–MAX6374Pin-Selectable Watchdog Timers_______________________________________________________________________________________5Pin DescriptionDetailed DescriptionThe MAX6369–MAX6374 are flexible watchdog circuits for monitoring µP activity. During normal operation, the internal timer is cleared each time the µP toggles the WDI with a valid logic transition (low to high or high to low) within the selected timeout period (t WD ). The WDO remains high as long as the input is strobed within the selected timeout period. If the input is not strobed before the timeout period expires, the watchdog output is asserted low for the watchdog output pulse width (t WDO ). The device type and the state of the three logic control pins (SET0, SET1, and SET2) determine watch-dog timing characteristics. The three basic timing varia-tions for the watchdog startup delay and the normalTable 1 for the timeout characteristics for all devices in the family):•Watchdog Startup Delay:Provides an initial delay before the watchdog timer is started.Allows time for the µP system to power up and initial-ize before assuming responsibility for normal watch-dog timer updates.Includes several fixed or pin-selectable startup delay options from 200µs to 60s, and an option to wait for the first watchdog input transition before starting the watchdog timer.M A X 6369–M A X 6374Pin-Selectable Watchdog Timers 6_______________________________________________________________________________________•Watchdog Timeout Period:Normal operating watchdog timeout period after the initial startup delay.A watchdog output pulse is asserted if a valid watch-dog input transition is not received before the timeout period elapses.Eight pin-selectable timeout period options for each device, from 30µs to 60s.Pin-selectable watchdog timer disable feature.•Watchdog Output/Timing Options:Open drain, active low with 100ms minimum watch-dog output pulse (MAX6369/MAX6371/MAX6373).Push-pull, active low with 1ms minimum watchdog output pulse (MAX6370/MAX6372/MAX6374).Each device has a watchdog startup delay that is initi-ated when the supervisor is first powered or after the user modifies any of the logic control set inputs. The watchdog timer does not begin to count down until theFigure 1. Functional Diagramcompletion of the startup delay period, and no watch-dog output pulses are asserted during the startup delay. When the startup delay expires, the watchdog begins counting its normal watchdog timeout period and waiting for WDI transitions. The startup delay allows time for the µP system to power up and fully ini-tialize before assuming responsibility for the normal watchdog timer updates. Startup delay periods vary between the different devices and may be altered by the logic control set pins. To ensure that the system generates no undesired watchdog outputs, the routine watchdog input transitions should begin before the selected minimum startup delay period has expired. The normal watchdog timeout period countdown is initi-ated when the startup delay is complete. If a valid logic transition is not recognized at WDI before the watchdog timeout period has expired, the supervisor asserts a watchdog output. Watchdog timeout periods vary between the different devices and may be altered by the logic control set pins. To ensure that the system generates no undesired watchdog outputs, the watch-dog input transitions should occur before the selected minimum watchdog timeout period has expired.The startup delay and the watchdog timeout period are determined by the states of the SET0, SET1, and SET2 pins, and by the particular device within the family. For the MAX6369 and MAX6370, the startup delay is equal to the watchdog timeout period. The startup and watchdog timeout periods are pin selectable from 1ms to 60s (minimum).For the MAX6371 and MAX6372, the startup delay is fixed at 60s and the watchdog timeout period is pin selectable from 1ms to 60s (minimum).The MAX6373/MAX6374 provide two timing variations for the startup delay and normal watchdog timeout. Five of the pin-selectable modes provide startup delays from 200µs to 60s minimum, and watchdog timeout delays from 3ms to 10s minimum. Two of the selectable modes do not initiate the watchdog timer until the device receives its first valid watchdog input transition (there is no fixed period by which the first input must be received). These two extended startup delay modesare useful for applications requiring more than 60s for system initialization.All the MAX6369–MAX6374 devices may be disabledwith the proper logic control pin setting (Table 1).Applications InformationInput Signal Considerations Watchdog timing is measured from the last WDI risingor falling edge associated with a pulse of at least 100nsin width. WDI transitions are ignored when WDO is asserted, and during the startup delay period (Figure2). Watchdog input transitions are also ignored for asetup period, t SETUP, of up to 300µs after power-up ora setting change (Figure 3).Selecting Device TimingSET2, SET1, and SET0 program the startup delay and watchdog timeout periods (Table 1). Timeout settingscan be hard wired, or they can be controlled with logicgates and modified during operation. To ensure smooth transitions, the system should strobe WDI immediately before the timing settings are changed. This minimizesthe risk of initializing a setting change too late in thetimer countdown period and generating undesired watchdog outputs. After changing the timing settings,two outcomes are possible based on WDO. If the change is made while WDO is asserted, the previous setting is allowed to finish, the characteristics of thenew setting are assumed, and the new startup phase is entered after a 300µs setup time (t SETUP) elapses. Ifthe change is made while WDO is not asserted, thenew setting is initiated immediately, and the new start-up phase is entered after the 300µs setup time elapses.MAX6369–MAX6374Pin-Selectable Watchdog Timers_______________________________________________________________________________________7 Figure 3. Setting Change TimingM A X 6369–M A X 6374Pin-Selectable Watchdog TimersSelecting 011 (SET2 = 0, SET1 = 1, SET0 = 1) disables the watchdog timer function on all devices in the family.Operation can be reenabled without powering down by changing the set inputs to the new desired setting. The device assumes the new selected timing characteris-tics and enter the startup phase after the 300µs setup time elapses (Figure 3).The MAX6373/MAX6374 offer a first-edge feature. In first-edge mode (settings 101 or 110, Table 1), the internal timer does not control the startup delay period.Instead, startup terminates when WDI sees a transition.If changing to first-edge mode while the device is oper-ating, disable mode must be entered first. It is then safe to select first-edge mode. Entering disable mode first ensures the output is unasserted when selecting first-edge mode and removes the danger of WDI being masked out.OutputThe MAX6369/MAX6371/MAX6373 have an active-low,open-drain output that provides a watchdog output pulse of 100ms. This output structure sinks current when WDO is asserted. Connect a pullup resistor from WDO to any supply voltage up to +5.5V.Select a resistor value large enough to register a logic low (see Ele ctrical Characte ristics ), and small enoughto register a logic high while supplying all input current and leakage paths connected to the WDO line. A 10k Ωpullup is sufficient in most applications. The MAX6370/MAX6372/MAX6374 have push-pull outputs that pro-vide an active-low watchdog output pulse of 1ms.When WDO deasserts, timing begins again at the beginning of the watchdog timeout period (Figure 2).Usage in Noisy EnvironmentsIf using the watchdog timer in an electrically noisy envi-ronment, a bypass capacitor of 0.1µF should be con-nected between V CC and GND as close to the device as possible, and no further away than 0.2 inches.________________Watchdog SoftwareConsiderationsTo help the watchdog timer monitor software execution more closely, set and reset the watchdog input at differ-ent points in the program, rather than pulsing the watch-dog input high-low-high or low-high-low. This technique avoids a stuck loop, in which the watchdog timer would continue to be reset inside the loop, keeping the watch-dog from timing out. Figure 4 shows an example of a flow diagram where the I/O driving the watchdog input is set high at the beginning of the program, set low at the end of every subroutine or loop, then set high again when the program returns to the beginning. If the pro-gram should hang in any subroutine, the problem would be quickly corrected, since the I/O is continually set low and the watchdog timer is allowed to time out, causing WDO to pulse.Figure 4. Watchdog Flow DiagramChip InformationTRANSISTOR COUNT: 1500PROCESS: BiCMOSPin ConfigurationMaxim cannot assume re sponsibility for use of any circuitry othe r than circuitry e ntire ly e mbodie d in a Maxim product. No circuit pate nt lice nse s are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2005 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products, Inc.。

max24033emy+t的规格书规格书：max24033emy+t一、产品介绍：max24033emy+t是一款高度集成的4通道电源管理IC，它主要用于工业控制系统、通信设备和数据中心等领域的电源管理。

该产品采用优质的半导体材料和先进的封装工艺，具有稳定可靠的性能和高效省电的特点。

二、产品特点：1.高度集成：max24033emy+t集成了4个高性能电源管理通道，包括电池充电管理、DC-DC转换器和电源监控等功能，可满足多种应用的需求。

2.宽输入电压范围：max24033emy+t支持广泛的输入电压范围，从3.5V到28V，能适应不同电源供应的要求。

3.高效节能：max24033emy+t采用了先进的能量管理技术，具有高效节能的特点，可以最大程度地减少能源浪费。

4.低功耗待机模式：max24033emy+t在待机模式下，功耗极低，能有效延长电池使用寿命。

5.温度保护：max24033emy+t具有自动温度保护功能，可在过热时自动停止工作，保护电路不受损坏。

6.电池管理：max24033emy+t支持电池充电和放电管理，能确保电池使用的安全和稳定性。

三、应用领域：max24033emy+t广泛应用于各种工业控制系统、通信设备和数据中心等领域，如智能家居、自动化控制、无线通信设备、数据存储等。

四、主要性能参数：1.输入电压范围：3.5V-28V2.输出电压范围：1.5V-16V3.输出电流范围：0A-3A4.工作温度范围：-40℃~85℃5.封装形式：QFN封装五、产品优势：1.优质材料：max24033emy+t采用优质的半导体材料和先进的封装工艺，保证了产品的稳定性和可靠性。

2.高效节能：max24033emy+t采用了先进的能量管理技术，具有高效节能的特点，能最大程度地减少能源浪费。

3.宽电压范围：max24033emy+t支持广泛的输入电压范围，能适应不同电源供应的要求。

4.多通道设计：max24033emy+t具有4个独立的电源管理通道，可满足多种应用的需求。

_______________General DescriptionThe MAX834/MAX835 micropower voltage monitors contain a 1.204V precision bandgap reference, com-parator, and latched output in a 5-pin SOT23 ing the latched output prevents deep discharge of batteries. The MAX834 has an open-drain, N-channel output driver, while the MAX835 has a push/pull output driver. Two external resistors set the trip-threshold voltage.The MAX834/MAX835 feature a level-sensitive latch,eliminating the need to add hysteresis to prevent oscil-lations in battery-load-disconnect applications.________________________ApplicationsPrecision Battery Monitor Load SwitchingBattery-Powered Systems Threshold Detectors____________________________Featureso Prevents Deep Discharge of Batteries o Precision ±1.25% Voltage Threshold o Latched Output (once low, stays low until cleared)o SOT23-5 Package o Low Costo Wide Operating Voltage Range, +2.5V to +11V o <2µA Typical Supply Current o Open-Drain Output (MAX834)Push/Pull Output (MAX835)MAX834/MAX835Micropower, Latching Voltage Monitorsin SOT23-5________________________________________________________________Maxim Integrated Products 1__________________Pin Configuration__________Typical Operating Circuit19-1157; Rev 0; 12/96______________Ordering InformationFor free samples & the latest literature: , or phone 1-800-998-8800M A X 834/M A X 835Micropower, Latching Voltage Monitors in SOT23-52_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +2.5V to +11V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC , OUT (MAX834), CLEAR to GND......................-0.3V to 12V IN, OUT (MAX835), to GND........................-0.3V to (V CC +0.3V)INPUT CurrentV CC .................................................................................20mA IN.....................................................................................10mA OUT Current.......................................................................-20mAV CC Rate of Rise .............................................................100V/µs Continuous Power DissipationSOT23-5 (derate 7.1mW/°C above +70°C)..................571mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10sec).............................+300°CMAX834/MAX835Micropower, Latching Voltage Monitorsin SOT23-5_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V CC = +2.5V to +11V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Note 1:The voltage-detector output remains in the correct state for V CC down to 1.2V when V IN ≤V CC / 2.Note 2:Supply current has a monotonic dependence on V CC (see Typical Operating Characteristics ).Note 3:IN leakage current has a monotonic dependence on V CC (see Typical Operating Characteristics ).Note 4:The MAX834 open-drain output can be pulled up to a voltage greater than V CC , but may not exceed 11V.__________________________________________Typical Operating Characteristics(V CC = +5V, Typical Operating Circuit, T A = +25°C, unless otherwise noted.)5.01.0-60-40020100INPUT LEAKAGE CURRENT vs. TEMPERATURE3.53.02.52.01.54.0TEMPERATURE (°C)I N P U T L E A K A G E C U R R E N T (n A )-204060804.590013489101112INPUT LEAKAGE CURRENT vs. INPUT VOLTAGE2010307080V IN (V)I N P U T L E A K A G E C U R R E N T (n A )2567405060 4.513489101112SUPPLY CURRENT vs. SUPPLY VOLTAGE1.51.00.52.04.0V CC (V)S U P P L Y C U R R E N T (µA )25672.53.03.562.4 2.83.2 3.6SUPPLY CURRENT vs. INPUT VOLTAGE5V IN (V)S U P P L Y C U R R E N T (µA )1.2210.40.8 2.041.6120013489101112SUPPLY CURRENT vs. INPUT VOLTAGE5432161011V IN (V)S U P P L Y C U R R E N T (µA )2567789 6.02.0-60-40020100PROGRAMMED TRIP VOLTAGEvs. TEMPERATURE3.22.82.43.65.25.6TEMPERATURE (°C)T R I P V O L T A G E (V )-204060804.04.44.8M A X 834/M A X 835Micropower, Latching Voltage Monitors in SOT23-54_______________________________________________________________________________________25013489101112MAX835OUTPUT SHORT-CIRCUITSOURCE CURRENT vs. SUPPLY VOLTAGE1510520V CC (V)S H O R T -C I R C U I T C U R R E N T (m A )256716040-60-40020100SUPPLY VOLTAGE FALLING TO OUT PROPAGATION DELAY vs. TEMPERATURE1301201101009080706050140TEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-204060801501000013489101112MAX835OUTPUT RISE TIME vs. SUPPLY VOLTAGE300200100400800900V CC (V)R I S E T I M E (n s )25675006007002.513489101112OUTPUT FALL TIME vs. SUPPLY VOLTAGE1.51.00.52.0V CC (V)F A L L T I M E (µs )25671101001k10k100k0.11100OUTPUT LOW VOLTAGE vs. OUTPUT SINK CURRENTOUTPUT SINK CURRENT (mA)V O L (m V )101101001k 10k 100k0.11100MAX835OUTPUT HIGH VOLTAGE vs. OUTPUT SOURCE CURRENTOUTPUT SOURCE CURRENT (mA)V C C - V O H (m V )1025013489101112OUTPUT LOW VOLTAGE vs. SUPPLY VOLTAGE15010050200V CC (V)V O L (m V )25675000134********MAX835OUTPUT HIGH VOLTAGE vs. SUPPLY VOLTAGE15010050200400450V CC (V)V C C - V O H (m V )25672503003502013489101112OUTPUT SHORT-CIRCUIT10515V CC (V)S H O R T -C I R C U I T C U R R E N T (m A )2567_____________________________Typical Operating Characteristics (continued)(V CC = +5V, Typical Operating Circuit, T A = +25°C, unless otherwise noted.)MAX834/MAX835Micropower, Latching Voltage Monitorsin SOT23-5_______________________________________________________________________________________5_____________________________Typical Operating Characteristics (continued)(V CC = +5V, Typical Operating Circuit, T A = +25°C, unless otherwise noted.)1101001k 10k0.1100OUTPUT LOW VOLTAGE vs. OUTPUT SINK CURRENTOUTPUT SINK CURRENT (mA)V O L (m V )1101101001k 10k 0.110MAX835OUTPUT HIGH VOLTAGE vs. OUTPUT SOURCE CURRENTOUTPUT SOURCE CURRENT (mA)V C C - V O H (m V )11.50.1-60-40020100CLEAR TO OUT PROPAGATION DELAYvs. TEMPERATURE0.90.70.50.31.1TEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-204060801.3______________________________________________________________Pin DescriptionOpen-Drain (MAX834) or Push/Pull (MAX835) Latched Output. OUT is active low.OUT5Noninverting Input to the Comparator. The inverting input connects to the internal 1.204V bandgap reference.IN 4System Supply InputV CC 3PINSystem Ground GND 2Clear Input resets the latched output. With V IN > V TH , pulse CLEAR high for a minimum of 1µs to reset the output latch. Connect to V CC to make the latch transparent.CLEAR 1FUNCTIONNAME Figure 1. Functional Diagram Figure 2. Programming the Trip Voltage (V TRIP )M A X 834/M A X 835Micropower, Latching Voltage Monitors in SOT23-56______________________________________________________________________________________________________Detailed DescriptionThe MAX834/MAX835 micropower voltage monitors con-tain a 1.204V precision bandgap reference and a com-parator with an output latch (Figure 1). The difference between the two parts is the structure of the comparator output driver. The MAX834 has an open-drain, N-channel output driver that can be pulled up to a voltage higher than V CC , but less than 11V. The MAX835’s output is push/pull and can both source and sink current.Programming the Trip Voltage (V TRIP )Two external resistors set the trip voltage, V TRIP (Figure 2). V TRIP is the point at which the falling monitored volt-age (typically V CC ) causes OUT to go low. IN’s high input impedance allows the use of large-value resistors without compromising trip voltage accuracy. To minimize current consumption, choose a value for R2between 500k Ωand 1M Ω, then calculate R1 as follows:R1 = R2 [(V TRIP / V TH ) - 1]where V TRIP is the desired trip voltage and V TH is the threshold voltage (1.204V). The voltage at IN must be at least 1V less than V CC .Latched-Output OperationThe MAX834/MAX835 feature a level-sensitive latch input (CLEAR), designed to eliminate the need for hys-teresis in battery undervoltage-detection applications.When the monitored voltage (V MON ) is above the pro-grammed trip voltage (V TRIP ) (as when the system bat-tery is recharged or a fresh battery is installed), pulse CLEAR low-high-low for at least 1µs to reset the output latch (OUT goes high). When V MON falls below V TRIP ,OUT goes low and remains low (even if V MON rises above V TRIP ), until CLEAR is pulsed high again with V MON > V TRIP . Figure 3 shows the timing relationship between V MON , OUT , and CLEAR.> V TRIP< V TRIPV CC0VOUTV MONFigure 3a. Timing DiagramFigure 3b. Timing Diagram, CLEAR = V CCMAX834/MAX835Micropower, Latching Voltage Monitorsin SOT23-5_______________________________________________________________________________________7Monitoring Voltages Other than V CCThe typical operating circuit for the MAX834/MAX835monitors V CC . Voltages other than V CC can easily be monitored, as shown in Figure 4. Calculate V TRIP as in the section Programming the Trip Voltage. When monitoring voltages other than V CC , ensure that the maximum value for V MON is not exceeded:V MON(MAX)= (V CC - 1)(R1 + R2) / R2Load-Disconnect SwitchThe circuit in Figure 5 is designed to prevent a lead-acid battery or a secondary battery such as an NiCd,from sustaining damage through deep discharge. As the battery reaches critical undervoltage, OUT switches low. Q1 and Q2 turn off, disconnecting the battery from the load. The MAX835’s latched output prevents Q1 and Q2 from turning on again as the battery voltage relaxes to its open-circuit voltage when the load disconnects.CLEAR can be connected to a pushbutton switch, an RC network, or a logic gate to reset the latch when the battery is recharged or replaced.Figure 4. Monitoring Voltages Other than V CCFigure 5. Load-Disconnect SwitchTRANSISTOR COUNT: 74___________________Chip InformationM A X 834/M A X 835Micropower, Latching Voltage Monitors in SOT23-5Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.8___________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600©1996 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.________________________________________________________________Package Information__________________________________________________Tape-and-Reel Information。

三通道测振仪VM-6380-3操 作 和 维 护 手 册使 用 说 明 书显示器：4位液晶显示器，用于显示数值和测量状态传感器：三个压电式振动传感器测量参数：速度、加速度及位移测量范围：速度：0.01-400.0 mm /s 真有效值0.004-16.00 inch/s 加速度：0.1-400.0m /s ² 峰值0.3-1312 ft/s ² ; 0.0-40g 位移：0.001-4.000mm 峰-峰值0.04-160.0 mil 准确度：±(5%n +2)个字输出：交流2.0V ,负载电阻10K关机: 2种模式，手动可随时关机，自动则在上次键盘操作5分钟后自动关机。

操作条件: 温度0-50℃ 湿度: < 95%尺寸: 140 x 73 x 35 mm 电源：4x 1.5vAAA 7#电池重量: 415 g （不含电池）标准配件：1. 磁性吸座........................1块2. 压电式振动传感器......... 3只3. 探针（锥型）……............1只4. 探针（球型）…...........….1只5. 手提便携箱.....................1只6. 使用说明书.....................1份可选配件：1. 耳机听诊器2. RS 232C 或USB 电缆和软件3. 蓝牙* 符合国际标准ISO 2954，GB 13823.3，用于周期性运动测量，以检测运动机械的不平衡和偏离。

* 专为现场测量各种机械振动而设计，以便为质量控制，运行时间及事先的设备维护提供数据。

* 选用高性能的三个压电加速计，可实现三维振动测量，准确度高、重复性好。

* 它具有轴承状况测量功能。

* 液晶LCD 显示，一个显示器可以同时显示三个测量点上的同一参数，或者任意一个测量点上的三种参数（加速度，速度，位移）。

* 重量轻，且操作简单，便于使用。

For free samples and the latest literature, visit or phone 1-800-998-8800.For small orders, phone 1-800-835-8769.General DescriptionThe MAX6361–MAX6364 supervisory circuits reduce the complexity and number of components required for power-supply monitoring and battery control functions in microprocessor (µP) systems. The circuits significantly improve system reliability and accuracy compared to that obtainable with separate ICs or discrete components.Their functions include µP reset, backup battery switchover, and power failure warning.The MAX6361–MAX6364 operate from supply voltages as low as +1.2V. The factory-preset reset threshold voltage ranges from 2.32V to 4.63V (see Ordering Information ).These devices provide a manual reset input (MAX6361),watchdog timer input (MAX6362), battery-on output (MAX6363), and an auxiliary adjustable reset input (MAX6364). In addition, each part type is offered in three reset output versions: an active-low open-drain reset, an active-low open-drain reset, and an active-high open-drain reset (see Selector Guide at end of data sheet).ApplicationsFeatures♦Low +1.2V Operating Supply Voltage (V CC or V BATT )♦Precision Monitoring of +5.0V, +3.3V, +3.0V, and +2.5V Power-Supply Voltages♦Debounced Manual Reset Input (MAX6361)♦Watchdog Timer with 1.6s Timeout Period (MAX6362)♦Battery-On Output Indicator (MAX6363)♦Auxiliary User-Adjustable RESET IN (MAX6364)♦Three Available Output StructuresPush-Pull RESET , Open-Drain RESET , Open-Drain RESET♦RESET/RESET Valid Down to 1.2V Guaranteed (V CC or V BATT )♦Power-Supply Transient Immunity ♦150ms (min) Reset Timeout Period ♦Small 6-Pin SOT23 PackageMAX6361–MAX6364SOT23, Low-Power µP Supervisory Circuitswith Battery Backup________________________________________________________________Maxim Integrated Products119-1615; Rev 3; 11/05Ordering InformationPin ConfigurationsFrom the table below, select the suffix corresponding to the desired threshold voltage and insert it into the part number to complete it. When ordering from the factory, there is a 2500-piece minimum on the SOT package (tape-and-reel only).Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing "-T" with "+T" when ordering.Computers ControllersIntelligent Instruments Critical µP/µC Power MonitoringFax Machines Industrial Control POS EquipmentPortable/Battery-Powered EquipmentSelector Guide appears at end of data sheet.Typical Operating Circuit appears at end of data sheet.M A X 6361–M A X 6364SOT23, Low-Power µP Supervisory Circuits with Battery BackupABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +2.4V to +5.5V, V BATT = 3V, T A = -40°C to +85°C, reset not asserted. Typical values are at T A = +25°C, unless otherwise noted.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Terminal Voltages (with respect to GND)V CC , BATT, OUT.......................................................-0.3V to +6V RESET (open drain), RESET (open drain)................-0.3V to +6V BATT ON, RESET (push-pull), RESET IN,WDI.......................................................-0.3V to (V OUT + 0.3V)MR .............................................................-0.3V to (V CC + 0.3V)Input CurrentV CC Peak ............................................................................1A V CC Continuous............................................................250mA BATT Peak....................................................................250mA BATT Continuous............................................................40mAGND................................................................................75mA Output CurrentOUT................................Short-Circuit Protection for up to 10s RESET, RESET , BATT ON ..............................................20mA Continuous Power Dissipation (T A = +70°C)6-Pin SOT23 (derate 8.70mW/°C above +70°C) .........696mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX6361–MAX6364SOT23, Low-Power µP Supervisory Circuitswith Battery Backup_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V CC = +2.4V to +5.5V, V BATT = 3V, T A = -40°C to +85°C, reset not asserted. Typical values are at T A = +25°C, unless otherwise noted.) (Note 1)Note 1:All devices are 100% production tested at T A = +25°C. Limits over temperature are guaranteed by design.Note 2:V BATT can be 0 anytime or V CC can go down to 0 if V BATT is active (except at startup).M A X 6361–M A X 6364SOT23, Low-Power µP Supervisory Circuits with Battery Backup 4_______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)1214161820SUPPLY CURRENT vs. TEMPERATURE(NO LOAD)TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )-402040-2060800.20.60.40.81.01.2BATTERY SUPPLY CURRENT (BACKUP MODE) vs. TEMPERATURETEMPERATURE (°C)B A T T E R Y S U P P L Y C U R R E N T (µA )-402040-20060801432567BATTERY TO OUT ON-RESISTANCEvs. TEMPERATURETEMPERATURE (°C)B A T T T O O U T O N -R E S I S T A NC E (Ω)-402040-20608000.30.90.61.2V CC TO OUT ON-RESISTANCEvs. TEMPERATURETEMPERATURE (°C)V O U T T O O U T O N -R E S I S T A N C E (Ω)-402040-206080190195205200210RESET TIMEOUT PERIOD vs. TEMPERATUREM A X 6361 t o c 05TEMPERATURE (°C)R E S E T T I M E O U T P E R I O D (m s )-402040-206080301575604513512010590V CC TO RESET PROPAGATION DELAYvs. TEMPERATURETEMPERATURE (°C)P R O P A G A T I O N D E LA Y (µs )-402040-2060802.03.02.55.04.54.03.5RESET THRESHOLD vs. TEMPERATURETEMPERATURE (°C)T H R E S H O L D (V )-402040-2060801.21.41.31.61.51.91.81.72.0-40-2020406080MAX6362WATCHDOG TIMEOUT PERIODvs. TEMPERATUREM A X 6361t o c 06aTEMPERATURE (°C)W A T C H D O G T I M E O U T P E R I O D (s )1100101k10kMAXIMUM TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVERESET THRESHOLD OVERDRIVE V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )400300350250200050150100MAX6361–MAX6364SOT23, Low-Power µP Supervisory Circuitswith Battery Backup1.2341.2351.236MAX6364RESET IN THRESHOLD vs. TEMPERATUREM A X 6361 t o c 10TEMPERATURE (°C)T H R E S H O L D (V )-402040-206080Typical Operating Characteristics (continued)(T A = +25°C, unless otherwise noted.)1.01.91.61.32.82.52.2MAX6364RESET IN TO RESET PROPAGATION DELAYvs. TEMPERATURETEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-402040-206080Pin Description0321456789101234BATTERY SUPPLY CURRENT vs. SUPPLY VOLTAGEV CC (V)B A T T E R Y S U P P L YC U R R E N T (µA )M A X 6361–M A X 6364Detailed DescriptionThe Typical Operating Circuit shows a typical connection for the MAX6361–MAX6364 family. OUT powers the stat-ic random-access memory (SRAM). OUT is internally connected to V CC if V CC is greater than the reset thresh-old, or to the greater of V CC or V BATT when V CC is less than the reset threshold. OUT can supply up to 150mA from V CC . When V CC is higher than V BATT , the BATT ON (MAX6363) output is low. When V CC is lower than V BATT ,an internal MOSF ET connects the backup battery to OUT. The on-resistance of the MOSFET is a function of backup-battery voltage and is shown in the Battery to Out On-Resistance vs. Temperature graph in the Typical Operating Characteristics section.Backup-Battery SwitchoverIn a brownout or power failure, it may be necessary to preserve the contents of the RAM. With a backup bat-tery installed at BATT, the MAX6361–MAX6364 auto-matically switch the RAM to backup power when V CC falls. The MAX6363 has a BATT ON output that goes high when in battery-backup mode. These devices require two conditions before switching to battery-backup mode:1)V CC must be below the reset threshold.2)V CC must be below V BATT .Table 1 lists the status of the inputs and outputs in bat-tery-backup mode. The device will not power up if the only voltage source is on BATT. OUT will only power up from V CC at startup.Manual Reset Input (MAX6361 Only)Many µP-based products require manual reset capabili-ty, allowing the operator, a test technician, or external logic circuitry to initiate a reset. For the MAX6361, a logic low on MR asserts reset. Reset remains asserted while MR is low, and for a minimum of 150ms (t RP ) after it returns high. MR has an internal 20k Ωpull-up resistor to V CC . This input can be driven with TTL/CMOS logic lev-els or with open-drain/collector outputs. Connect a nor-mally open momentary switch from MR to GND to create a manual reset function; external debounce circuitry is not required. If MR is driven from long cables or the device is used in a noisy environment, connect a 0.1µF capacitor from MR to GND to provide additional noise immunity.Watchdog Input (MAX6362 Only)The watchdog monitors µP activity through the input WDI. If the µP becomes inactive, the reset output is asserted in pulses. To use the watchdog function, con-nect WDI to a bus line or µP I/O line. A change of state(high to low or low to high) within the watchdog timeout period (t WD ) with a 100ns minimum pulse width clears the watchdog timer. If WDI remains high or low for longer than the watchdog timeout period, the internal watchdog timer runs out and a reset pulse is triggered for the reset timeout period (t RP ). The internal watchdog timer clears whenever reset asserts or the WDI sees a rising or falling edge within the watchdog timeout period. If WDI remains in a high or low state for an extended period of time, a reset pulse asserts after every watchdog timeout period (t WD ) (Figure 1).Reset In (MAX6364 Only)RESET IN is compared to an internal 1.235V reference.If the voltage at RESET IN is less than 1.235V, reset is asserted. The RESET IN comparator may be used as an undervoltage detector to signal a failing power sup-ply. It can also be used as a secondary power-supply reset monitor.To program the reset threshold (V RTH ) of the secondary power supply, use the following equation (see Typical Operating Circuit ):where V REF = 1.235V. To simplify the resistor selection,choose a value for R2 and calculate R1:Since the input current at RESET IN is 25nA (max), large values (up to 1M Ω) can be used for R2 with no signifi-cant loss in accuracy. F or example, in the TypicalSOT23, Low-Power µP Supervisory Circuits with Battery Backup 6_______________________________________________________________________________________R R V V RTH REF 121 /=()−[]MAX6361–MAX6364SOT23, Low-Power µP Supervisory Circuitswith Battery Backup_______________________________________________________________________________________7Operating Circuit,the MAX6362 monitors two supply voltages. To monitor the secondary 5V logic or analog supply with a 4.60V nominal programmed reset thresh-old, choose R2 = 100k Ω, and calculate R1 = 273k Ω.Reset OutputA µP’s reset input starts the µP in a known state. The MAX6361–MAX6364 µP supervisory circuits assert a reset to prevent code-execution errors during power-up, power-down, and brownout conditions. RESET is guaranteed to be a logic low or high depending on the device chosen (see Ordering Information ). RESET or RESET asserts when V CC is below the reset threshold and for at least 150ms (t RP ) after V CC rises above the reset threshold. RESET or RESET also asserts when MR is low (MAX6361) and when RESET IN is less than 1.235V (MAX6364). The MAX6362 watchdog function will cause RESET (or RESET ) to assert in pulses follow-ing a watchdog timeout (Figure 1).Applications InformationOperation Without a BackupPower SourceThe MAX6361–MAX6364 were designed for battery-backed applications. If a backup battery is not used,connect V CC to OUT and connect BATT to GND.Replacing the Backup BatteryIf BATT is decoupled with a 0.1µF capacitor to ground,the backup power source can be removed while V CC remains valid without danger of triggering a reset pulse.The device does not enter battery-backup mode when V CC stays above the reset threshold voltage.Negative-Going V CC TransientsThese supervisors are relatively immune to short-dura-tion, negative-going V CC transients. Resetting the µPwhen V CC experiences only small glitches is usually not desirable.The Typical Operating Characteristics section shows a graph of Maximum Transient Duration vs. Reset Threshold Overdrive for which reset is not asserted.The graph was produced using negative-going V CC pulses, starting at V CC and ending below the reset threshold by the magnitude indicated (reset threshold overdrive). The graph shows the maximum pulse width that a negative-going V CC transient can typically have without triggering a reset pulse. As the amplitude of the transient increases (i.e., goes further below the reset threshold), the maximum allowable pulse width decreases. Typically, a V CC transient that goes 100mV below the reset threshold and lasts for 30µs will not trigger a reset pulse.A 0.1µF bypass capacitor mounted close to the V CC pin provides additional transient immunity.Figure 1. MAX6362 Watchdog Timeout Period and Reset Active TimeM A X 6361–M A X 6364Watchdog Software Considerations(MAX6362 Only)To help the watchdog timer monitor software execution more closely, set and reset the watchdog input at dif-ferent points in the program, rather than “pulsing” the watchdog input low-high-low. This technique avoids a “stuck” loop, in which the watchdog timer would contin-ue to be reset within the loop, keeping the watchdog from timing out. F igure 2 shows an example of a flow diagram where the I/O driving the WDI is set low at the beginning of the program, set high at the beginning of every subroutine or loop, then set low again when the program returns to the beginning. If the program should “hang” in any subroutine, the problem would quickly be corrected, since the I/O is continually set low and the watchdog timer is allowed to time out, trigger-ing a reset.SOT23, Low-Power µP Supervisory Circuits with Battery Backup 8_______________________________________________________________________________________Figure 2. Watchdog Flow DiagramMAX6361–MAX6364SOT23, Low-Power µP Supervisory Circuitswith Battery Backup_______________________________________________________________________________________9*Sample stock generally held on standard versions only. Contact factory for availability of nonstandard versions.Device Marking CodesSelector GuideM A X 6361–M A X 6364SOT23, Low-Power µP Supervisory Circuits with Battery Backup 10______________________________________________________________________________________Pin Configurations (continued)Typical Operating CircuitChip InformationTRANSISTOR COUNT: 720MAX6361–MAX6364SOT23, Low-Power µP Supervisory Circuits with Battery Backup______________________________________________________________________________________11Package InformationM A X 6361–M A X 6364SOT23, Low-Power µP Supervisory Circuits with Battery BackupMaxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.12____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.NOTES。

General DescriptionThe MAX6397/MAX6398 are small, high-voltage overvolt-age protection circuits. These devices disconnect the output load or limit the output voltage during an input overvoltage condition. These devices are ideal for appli-cations that must survive high-voltage transients such as those found in automotive and industrial applications.The MAX6397/MAX6398 monitor the input or output voltages and control an external n-channel MOSFET to isolate or limit the load from overvoltage transient energy.When the monitored input voltage is below the user-adjustable overvoltage threshold, the external n-channel MOSFET is turned on by the GATE output. In this mode,the internal charge pump fully enhances the n-channel MOSFET with a 10V gate-to-source voltage.When the input voltage exceeds the overvoltage thresh-old, the protection can disconnect the load from the input by quickly forcing the GATE output low. In some applications, disconnecting the output from the load is not desirable. In these cases, the protection circuit can be configured to act as a voltage limiter where the GATE output sawtooths to limit the voltage to the load.The MAX6397 also offers an always-on linear regulator that is capable of delivering up to 100mA of output current. This high-voltage linear regulator consumes only 37µA of quiescent current.The regulator is offered with output options of 5V, 3.3V,2.5V, or 1.8V. An open-drain, power-good output (POK)asserts when the regulator output falls below 92.5% or 87.5% of its nominal voltage.The MAX6397/MAX6398 include internal thermal-shut-down protection, disabling the external MOSF ET and linear regulator if the chip reaches overtemperature conditions. The devices operate over a wide 5.5V to 72V supply voltage range, are available in small TDFN packages, and are fully specified from -40°C to +125°C.ApplicationsAutomotive Industrial FireWire ®Notebook Computers Wall Cube Power DevicesFeatures♦5.5V to 72V Wide Supply Voltage Range♦Overvoltage Protection Controllers Allow User to Size External n-Channel MOSFETs ♦Internal Charge-Pump Circuit Ensures MOSFET Gate-to-Source Enhancement for Low R DS(ON)Performance ♦Disconnect or Limit Output from Input During Overvoltage Conditions ♦Adjustable Overvoltage Threshold ♦Thermal-Shutdown Protection♦Always-On, Low-Current (37µA) Linear Regulator Sources Up to 100mA (MAX6397)♦Fully Specified from -40°C to +125°C (T J )♦Small, Thermally Enhanced 3mm x 3mm TDFN PackageMAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V________________________________________________________________Maxim Integrated Products1Pin ConfigurationsOrdering Information19-3668; Rev 3; 1/07For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Selector Guide and Typical Operating Circuit appear at end of data sheet.FireWire is a registered trademark of Apple Computer, Inc.M A X 6397/M A X 6398Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V= 14V; C = 6000pF, C = 4.7µF, T = T = -40°C to +125°C, unless otherwise noted. Typical values are at T = T = +25°C.)(Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional oper-ation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.(All pins referenced to GND, unless otherwise noted.)IN, GATE, OUT............................................................-0.3V to +80V SHDN ..................................................................-0.3V to (IN + 0.3V)GATE to OUT.................................................................-0.3 to +20V SET, REG, POK...........................................................-0.3V to +12V Maximum Current:IN, REG...............................................................................350mA All Remaining Pins...................................................................50mAContinuous Power Dissipation (T A = +70°C)6-Pin TDFN (derate 18.2mW/°C above +70°C).............1455mW 8-Pin TDFN (derate 18.2mW/°C above +70°C).............1455mW Operating Temperature Range (T A )......................-40°C to +125°C Junction Temperature...........................................................+150°C Storage Temperature Range.................................-65°C to +150°C Lead Temperature................................................................+300°CMAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V IN = 14V; C GATE = 6000pF, C REG = 4.7µF, T A = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A = T J = +25°C.)(Note 1)Note 1:Specifications to -40°C are guaranteed by design and not production tested.Note 2:The MAX6397/MAX6398 power up with the external FET in off mode (V GATE = GND). The external FET turns on t START after thedevice is powered up and all input conditions are valid.Note 3:For accurate overtemperature shutdown performance, place the device in close thermal contact with the external MOSFET.Note 4:Dropout voltage is defined as V IN - V REG when V REG is 2% below the value of V REG for V IN = V REG (nominal) + 2V.Note 5:Operations beyond the thermal dissipation limit may permanently damage the device.M A X 6397/M A X 6398Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 4_______________________________________________________________________________________Typical Operating Characteristics(V IN = 14V, C REG = 4.7µF, I REG = 0, unless otherwise noted.)40608010012014016002010304050607080SUPPLY CURRENT vs. INPUT VOLTAGEINPUT VOLTAGE (V)S U P P L Y C U R R E N T (µA )SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )1007525500-259010011012013014015016017018080-50125405060708090100110120020406080SUPPLY CURRENT vs. INPUT VOLTAGEINPUT VOLTAGE (V)S U P P L Y CU R R E N T (µA )8010090120110130140-502550-25075100125SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L YC U R R E N T (µA )20302540354550040206080SHUTDOWN SUPPLY CURRENT vs. INPUT VOLTAGE (MAX6397)INPUT VOLTAGE (V)S U P P L YC U R R E N T (µA )103050700642810121416182020406080SHUTDOWN SUPPLY CURRENTvs. INPUT VOLTAGEINPUT VOLTAGE (V)S U P PL Y C U R R E N T (µA )0642810124121068141618202224GATE-DRIVE VOLTAGE vs. INPUT VOLTAGEINPUT VOLTAGE (V)V G A T E - V O U T (V )4.04.64.44.25.04.85.85.65.45.26.0-50-250255075100125UVLO THRESHOLD vs. TEMPERATUREM A X 6397-98 t o c 08TEMPERATURE (°C)V U V L O (V )SET THRESHOLD vs. TEMPERATUREM A X 6397-98 t o c 09TEMPERATURE (°C)S E T T H R E S H O L D (V )1007525500-251.2041.2081.2121.2161.2201.2241.2281.2321.2361.2401.200-50125MAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V_______________________________________________________________________________________516.016.316.216.116.516.416.916.816.716.617.0-50-25255075100125GATE-TO-OUT CLAMP VOLTAGEvs. TEMPERATUREM A X 6397-98 t o c 10TEMPERATURE (°C)G A T E -T O -O U T C L A M P V O L T A G E (V )00.40.20.80.61.21.01.41.81.62.0040608020100120140160180DROPOUT VOLTAGE vs. REG LOAD CURRENTREG LOAD CURRENT (mA)D R O P O U T V O L T A GE (V )4.905.004.955.105.055.155.20-40-10520-253550658095110125REG OUTPUT VOLTAGEvs. LOAD CURRENT AND TEMPERATURETEMPERATURE (°C)R E G O U T P U T V O L T A G E (V )4.04.64.44.24.85.05.21601204080200240280320360400MAXIMUM REG OUTPUT VOLTAGE vs. LOAD CURRENT AND TEMPERATURELOAD CURRENT (mA)R E G O U T P U T V O L T A G E (V )POWER-SUPPLY REJECTION RATIOvs. FREQUENCYFREQUENCY (Hz)P S R R (d B )1M 100k 10k 1k 100-60-50-40-30-20-100-701010M4ms/divSTARTUP WAVEFORM(R LOAD = 100Ω, C IN = 10µF, C OUT = 10µF)V IN 10V/divMAX6397-98 toc16V GATE 10V/div V OUT 10V/div I OUT200mA/div400µs/divSTARTUP WAVEFORM FROM SHUTDOWN(C IN = 10µF, C OUT = 10µF)V 2V/divV GATE 10V/divV OUT 10V/div I OUT200mA/divR LOAD = 100ΩTypical Operating Characteristics (continued)(V IN = 14V, C REG = 4.7µF, I REG = 0, unless otherwise noted.)GATE-DRIVE VOLTAGE vs. TEMPERATUREM A X 6397-98 t o c 14TEMPERATURE (°C)G A T E -D R I V E V O L T A G E (V )1007525500-2510.45510.46010.46510.47010.47510.48010.48510.49010.49510.50010.450-50125M A X 6397/M A X 6398Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 6_______________________________________________________________________________________Typical Operating Characteristics (continued)(V IN = 14V, C REG = 4.7µF, I REG = 0, unless otherwise noted.)200µs/divOVERVOLTAGE SWITCH FAULTV IN 20V/divV GATE 20V/div V OUT 20V/div V REG 5V/divV OV = 30V1ms/divVOLTAGE LIMIT FAULTV IN 20V/divV GATE 20V/divV OUT 20V/div V REG 5V/divV OV = 30V400µs/divTRANSIENT RESPONSEV IN 10V/divV REG100mV/divC REG = 10µF I REG = 10mA1ms/divREG LOAD-TRANSIENT RESPONSEV REGAC-COUPLED 500mV/divI REG100mA/divC REG = 10µF1ms/divREGULATOR STARTUP WAVEFORMV IN 10V/divV POK 2V/divV REG 2V/divI REG = 10mA100µs/divREGULATOR POK ASSERTIONV REG 2V/divI REG200mA/div V POK 2V/divI REG = 00V0V0ADetailed Description The MAX6397/MAX6398 are ultra-small, low-current, high-voltage protection circuits for automotive applica-tions that must survive load dump and high-voltage transient conditions. These devices monitor the input/ output voltages and control an external n-channel MOSF ET to isolate the load or to regulate the output voltage from overvoltage transient energy. The con-troller allows system designers to size the external MOSFET to their load current and board size.The MAX6397/MAX6398 drive the MOSF ET’s gate high when the monitored input voltage is below the adjustable overvoltage threshold. An internal charge-pump circuit provides a 5V to 10V gate-to-source drive (see the Typical Operating Characteristics) to ensure low input-to-load voltage drops in normal operating modes. When the input voltage rises above the user-adjusted overvoltage threshold, GATE pulls to OUT, turning off the MOSFET.The MAX6397/MAX6398 are configurable to operate as overvoltage protection switches or as closed-looped volt-age limiters. In overvoltage protection switch mode, theinput voltage is monitored. When an overvoltage condi-tion occurs at IN, GATE pulls low, disconnecting the loadfrom the power source, and then slowly enhances upon removal of the overvoltage condition. In overvoltagelimit mode, the output voltage is monitored and theMAX6397/MAX6398 regulate the source of the external MOSFET at the adjusted overvoltage threshold, allowing devices within the system to continue operating during an overvoltage condition.The MAX6397/MAX6398 undervoltage lockout (UVLO) function disables the devices as long as the input remains below the 5V (typ) UVLO turn-on threshold. TheMAX6397/MAX6398 have an active-low SHDN input toturn off the external MOSFET, disconnecting the load and reducing power consumption. After power is applied and SHDN is driven above its logic-high voltage, there is a100µs delay before GATE enhancement commences.MAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V _______________________________________________________________________________________7M A X 6397/M A X 6398The MAX6397 integrates a high-input-voltage, low-qui-escent-current linear regulator in addition to an over-voltage protector circuit. The linear regulator remains enabled at all times to power low-current “always-on”applications (independent of the state of the external MOSF ET). The regulator is offered with several stan-dard output voltage options (5V, 3.3V, 2.5V, or 1.8V).An open-drain power-good output notifies the system if the regulator output falls to 92.5% or 87.5% of its nomi-nal voltage. The MAX6397’s REG output operates inde-pendently of the SHDN logic input.The MAX6397/MAX6398 include internal thermal-shut-down protection, disabling the external MOSF ET and linear regulator if the chip reaches overtemperature conditions.Linear Regulator (MAX6397 Only)The MAX6397 is available with 5.0V, 3.3V, 2.5V, and 1.8V factory-set output voltages. Each regulator sources up to 100mA and includes a current limit of 230mA. The linear regulator operates in an always-on condition regardless of the SHDN logic. For fully specified operation, V IN must be greater than 6.5V for the MAX6397L/M (5V regulator output). The actual output current may be limited by the operating condition and package power dissipation.Power-OK OutputPOK is an open-drain output that goes low when REG falls to 92.5% or 87.5% (see the Selector Guide ) of its nominal output voltage. To obtain a logic-level output,connect a pullup resistor from POK to REG or another system voltage. Use a resistor in the 100k Ωrange to minimize current consumption. POK provides a valid logic-output level down to V IN = 1.5V.GATE VoltageThe MAX6397/MAX6398 use a high-efficiency charge pump to generate the GATE voltage. Upon V IN exceed-ing the 5V (typ) UVLO threshold, GATE enhances 10V above IN (for V IN ≥14V) with a 75µA pullup current. An overvoltage condition occurs when the voltage at SET pulls above its 1.215V threshold. When the threshold is crossed, GATE falls to OUT within 100ns with a 100mA (typ) pulldown current. The MAX6397/MAX6398 include an internal clamp to OUT that ensures GATE is limited to 18V (max) above OUT to prevent gate-to-source damage to the external FET.The GATE cycle during overvoltage limit and overvolt-age switch modes are quite similar but have distinct characteristics. In overvoltage switch mode (Figure 2a),GATE is enhanced to V IN + 10V while the monitored IN voltage remains below the overvoltage fault threshold (SET < 1.215V). When an overvoltage fault occurs (SET ≥1.215V), GATE is pulled one diode below OUT, turn-ing off the external F ET and disconnecting the load from the input. GATE remains low (FET off) as long as V IN is above the overvoltage fault threshold. As V IN falls back below the overvoltage fault threshold (-5% hys-teresis) GATE is again enhanced to V IN + 10V.In overvoltage limit mode (Figure 2b), GATE is enhanced to V IN + 10V. While the monitored OUT voltage remains below the overvoltage fault threshold (SET < 1.215V).When an overvoltage fault occurs (SET ≥1.215V),GATE is pulled low one diode drop below OUT until OUT drops 5% below the overvoltage fault threshold.GATE is then turned back on until OUT again reaches the overvoltage fault threshold and GATE is again turned off.Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 8_______________________________________________________________________________________GATE cycles on-off-on-off-on in a sawtooth waveform until OUT remains below the overvoltage fault threshold and GATE remains constantly on (V IN + 10V). The over-voltage limiter’s sawtooth GATE output operates the MOSFET in a switched-linear mode while the input volt-age remains above the overvoltage fault threshold. The sawtooth frequency depends on the load capacitance,load current, and MOSFET turn-on time (GATE charge current and GATE capacitance).GATE goes high when the following startup conditions are met: V IN is above the UVLO threshold, SHDN is high, an overvoltage fault is not present and the device is not in thermal shutdown.Overvoltage MonitoringWhen operating in overvoltage mode, the MAX6397/MAX6398 feedback path (F igure 3) consists of IN,SET’s internal comparator, the internal gate charge pump, and the external n-channel MOSFET resulting in a switch-on/off function. When the programmed over-voltage threshold is tripped, the internal fast compara-tor turns off the external MOSFET, pulling GATE to OUT within t OV and disconnecting the power source from the load. When IN decreases below the adjusted over-voltage threshold, the MAX6397/MAX6398 slowly enhance GATE above OUT, reconnecting the load to the power source.Overvoltage LimiterWhen operating in overvoltage limiter mode, the MAX6397/MAX6398 feedback path (F igure 4) consists of OUT, SET’s internal comparator, the internal gate charge pump and the external n-channel MOSF ET,which results in the external MOSF ET operating as a voltage regulator.During normal operation, GATE is enhanced 10V above OUT. The external MOSFET source voltage is monitored through a resistor-divider between OUT and SET. When OUT rises above the adjusted overvoltage threshold, an internal comparator sinks the charge-pump current, dis-charging the external GATE, regulating OUT at the set overvoltage threshold. OUT remains active during the overvoltage transients and the MOSFET continues to con-duct during the overvoltage event, operating in switched-linear mode.MAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V_______________________________________________________________________________________9V GATE 10V/divV OUT 10V/divV IN 10V/div10ms/divV GATE 10V/divV OUT 10V/divV IN 10V/div4ms/divM A X 6397/M A X 6398As the transient begins decreasing, OUT fall time will depend on the MOSF ET’s GATE charge, the internal charge-pump current, the output load, and the tank capacitor at OUT.For fast-rising transients and very large-sized MOSFETs,add an additional external bypass capacitor from GATE to GND to reduce the effect of the fast-rising voltages at IN. The external capacitor acts as a voltage-divider working against the MOSF ETs’ drain-to-gate capaci-tance. For a 6000pF C gd , a 0.1µF capacitor at GATE will reduce the impact of the fast-rising V IN input.Caution must be exercised when operating the MAX6397/MAX6398 in voltage-limiting mode for long durations. If the V IN is a DC voltage greater than the MOSFET’s maximum gate voltage, the FET will dissipate power continuously. To prevent damage to the external MOSFET, proper heatsinking should be implemented.Applications InformationLoad DumpMost automotive applications run off a multicell, 12V lead-acid battery with a nominal voltage that swings between 9V and 16V (depending on load current,charging status, temperature, battery age, etc.). The battery voltage is distributed throughout the automobile and is locally regulated down to voltages required by the different system modules. Load dump occurs when the alternator is charging the battery and the battery becomes disconnected. Power in the alternator (essen-tially an inductor) flows into the distributed power sys-tem and elevates the voltage seen at each module. The voltage spikes have rise times typically greater than 5ms and decays within several hundred milliseconds but can extend out to 1s or more depending on thecharacteristics of the charging system (F igure 5).These transients are capable of destroying semicon-ductors on the first ‘fault event.’Setting Overvoltage ThresholdsSET provides an accurate means to set the overvoltage level for the MAX6397/MAX6398. Use a resistor-divider to set the desired overvoltage condition (Figure 6). SET has a rising 1.215V threshold with a 5% falling hysteresis.Begin by selecting the total end-to-end resistance,R TOTAL = R1 + R2. Choose R TOTAL to yield a total cur-rent equivalent to a minimum 100 x I SET (SET’s input bias current) at the desired overvoltage threshold.For example:With an overvoltage threshold set to 20V:R TOTAL < 20V/(100 x I SET )where I SET is SET’s 50nA input bias current.R TOTAL < 4M ΩUse the following formula to calculate R2:where V TH is the 1.215V SET rising threshold and V OV is the overvoltage threshold.R2 = 243k Ω, use a 240k Ωstandard resistor.R TOTAL = R2 + R1, where R1 = 3.76M Ω.Use a 3.79M Ωstandard resistor.A lower value for total resistance dissipates morepower but provides slightly better accuracy.Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 10______________________________________________________________________________________Reverse-Battery ProtectionUse a diode or p-channel MOSF ET to protect the MAX6397/MAX6398 during a reverse-battery insertion (Figures 7a, 7b). Low p-channel MOSFET on-resistance of 30m Ωor less yields a forward-voltage drop of only a few millivolts (versus hundreds of millivolts for a diode,Figure 7a) thus improving efficiency.Connecting a positive battery voltage to the drain of Q1(F igure 7b) produces forward bias in its body diode,which clamps the source voltage one diode drop below the drain voltage. When the source voltage exceeds Q1’s threshold voltage, Q1 turns on. Once the F ET is on, the battery is fully connected to the system and can deliver power to the device and the load.An incorrectly inserted battery reverse-biases the F ET’s body diode. The gate remains at the ground potential.The FET remains off and disconnects the reversed bat-tery from the system. The zener diode and resistor com-bination prevent damage to the p-channel MOSF ET during an overvoltage condition.MAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V______________________________________________________________________________________11M A X 6397/M A X 6398REG Capacitor Selection for StabilityFor stable operation over the full temperature range and with load currents up to 100mA, use ceramic capacitor values greater than 4.7µF. Large output capacitors help reduce noise, improve load-transient response, and power-supply rejection at REG. Note that some ceramic dielectrics exhibit large capacitance and ESR variation with temperature. At lower temperatures, it may be nec-essary to increase capacitance.Under normal conditions, use a 10µF capacitor at rger input capacitor values and lower ESR provide bet-ter supply-noise rejection and line-transient response.Inrush/Slew-Rate ControlInrush current control can be implemented by placing a capacitor at GATE (F igure 8) to slowly ramp up the GATE, thus limiting the inrush current and controlling GATE’s slew rate during initial turn-on. The inrush cur-rent can be approximated using the following formula:where I GATE is GATE’s 75µA sourcing current, I LOAD is the load current at startup, and C OUT is the output capacitor.Input Transients ClampingWhen the external MOSFET is turned off during an over-voltage occurrence, stray inductance in the power path may cause voltage ringing exceeding the MAX6397/MAX6398 absolute maximum input (IN) supply rating.The following techniques are recommended to reduce the effect of transients:•Minimize stray inductance in the power path usingwide traces, and minimize loop area including the power traces and the return ground path.•Add a zener diode or transient voltage suppressor(TVS) rated below the IN absolute maximum rating (Figure 9).Add a resistor in series with IN to limit transient currentgoing into the input for the MAX6398 only.Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 12______________________________________________________________________________________Figure 8. MAX6397/MAX6398 Controlling GATE Inrush CurrentFigure 9. Protecting the MAX6397/MAX6398 Input from High-Voltage TransientsMOSFET SelectionSelect external MOSF ETs according to the application current level. The MOSF ET’s on-resistance (R DS(ON))should be chosen low enough to have minimum voltage drop at full load to limit the MOSFET power dissipation.Determine the device power rating to accommodate an overvoltage fault when operating the MAX6397/MAX6398 in overvoltage limit mode.During normal operation, the external MOSFETs dissipate little power. The power dissipated in normal operation is:P Q1 = I LOAD 2x R DS(ON).The most power dissipation will occur during a pro-longed overvoltage event when operating the MAX6397/MAX6398 in voltage limiter mode, resulting in high power dissipated in Q1 (F igure 10) where the power dissipated across Q1 is:P Q1= V Q1x I LOADwhere V Q1is the voltage across the MOSF ET’s drain and source.Thermal ShutdownThe MAX6397/MAX6398 thermal-shutdown feature shuts off the linear regulator output, REG, and GATE if it exceeds the maximum allowable thermal dissipation.Thermal shutdown also monitors the PC board tempera-ture of the external nF ET when the devices sit on thesame thermal island. Good thermal contact between the MAX6397/MAX6398 and the external nF ET is essential for the thermal-shutdown feature to operate effectively.Place the nFET as close as possible to OUT.When the junction temperature exceeds T J = +150°C,the thermal sensor signals the shutdown logic, turning off REG’s internal pass transistor and the GATE output,allowing the device to cool. The thermal sensor turns the pass transistor and GATE on again after the IC’s junction temperature cools by 20°C. Thermal-overload protection is designed to protect the MAX6397/MAX6398 and the external MOSFET in the event of cur-rent-limit fault conditions. For continuous operation, do not exceed the absolute maximum junction-tempera-ture rating of T J = +150°C.Thermal ShutdownOvervoltage Limiter ModeWhen operating the MAX6397/MAX6398 in overvoltage limit mode for a prolonged period of time, a thermal shutdown is possible due to device self-heating. The thermal shutdown is dependent on a number of differ-ent factors:•The device’s ambient temperature (T A )•The output capacitor (C OUT )•The output load current (I OUT )•The overvoltage threshold limit (V OV )•The overvoltage waveform period (t OVP )•The power dissipated across the package (P DISS )MAX6397/MAX6398Overvoltage Protection Switch/LimiterControllers Operate Up to 72V______________________________________________________________________________________13M A X 6397/M A X 6398When OUT exceeds the adjusted overvoltage threshold,an internal GATE pulldown current is enabled until OUT drops by 5%. The capacitance at OUT is discharged by the internal current sink and the external OUT load cur-rent. The discharge time (∆t1) is approximately:where V OV is the adjusted overvoltage threshold, I OUT is the external load current and I GATEPD is the GATE’s internal 100mA (typ) pulldown current.When OUT falls 5% below the overvoltage threshold point, the internal current sink is disabled and the MAX6397/MAX6398’s internal charge pump begins recharging the external GATE voltage. The OUT volt-age continues to drop due to the external OUT load current until the MOSF ET gate is recharged. The time needed to recharge GATE and re-enhance the external nFET is approximately:where C ISS is the MOSFET’s input capacitance, V GS(TH)is the MOSFET’s gate-to-source threshold voltage, V F is the internal clamp diode forward voltage (V F = 1.5V typ),and I GATE is the MAX6397/MAX6398 charge-pump cur-rent (75µA typ).During ∆t2, C OUT loses charge through the output load.The voltage across C OUT (∆V2) decreases until the MOSF ET reaches its V GS(TH) threshold and can be approximated using the following formula:Once the MOSFET V GS (TH ) is obtained, the slope of the output voltage rise is determined by the MOSF ET Q G charge through the internal charge pump with respect to the drain potential. The time for the OUT voltage to rise again to the overvoltage threshold can be approxi-mated using the following formula:where ∆V OUT = ( V OV x 0.05) + ∆V2.The total period of the overvoltage waveform can be summed up as follows:t OVP = ∆t1 + ∆t2 + ∆t3The MAX6397/MAX6398 dissipate the most power dur-ing an overvoltage event when I OUT = 0 (C OUT is dis-charged only by the internal current sink). The maximum power dissipation can be approximated using the follow-ing equation:The die temperature (T J ) increase is related to θJC (8.3°C/W and 8.5°C/W for the MAX6397 and MAX6398,respectively) of the package when mounted correctly with a strong thermal contact to the circuit board. The MAX6397/MAX6398 thermal shutdown is governed by the equation:T J = T A + P DISS x (θJC + θCA) < 170°C (typical thermal-shutdown temperature)For the MAX6397, the power dissipation of the internal linear regulator must be added to the overvoltage pro-tection circuit power dissipation to calculate the die temperature. The linear regulator power dissipation is calculated using the following equation:P REG = (V IN – V REG ) (I REG )F or example, using an IRF R3410 100V n-channel MOSF ET, F igure 12 illustrates the junction temperature vs. output capacitor with I OUT = 0, T A = +125°C, V OV < 16V,V F = 1.5V, I GATE = 75mA, and I GATEPD =100mA. Figure 12 shows the relationship between output capacitance versus die temperature for the conditionslisted above.Overvoltage Protection Switch/Limiter Controllers Operate Up to 72V 14______________________________________________________________________________________。

用于Peltier模块的集成温度控制器概论MAX1978 / MAX1979是用于Peltier热电冷却器（TEC）模块的最小, 最安全, 最精确完整的单芯片温度控制器。

片上功率FET和热控制环路电路可最大限度地减少外部元件, 同时保持高效率。

可选择的500kHz / 1MHz开关频率和独特的纹波消除方案可优化元件尺寸和效率, 同时降低噪声。

内部MOSFET的开关速度经过优化, 可降低噪声和EMI。

超低漂移斩波放大器可保持±0.001°C的温度稳定性。

直接控制输出电流而不是电压, 以消除电流浪涌。

独立的加热和冷却电流和电压限制提供最高水平的TEC保护。

MAX1978采用单电源供电, 通过在两个同步降压调节器的输出之间偏置TEC, 提供双极性±3A输出。

真正的双极性操作控制温度, 在低负载电流下没有“死区”或其他非线性。

当设定点非常接近自然操作点时, 控制系统不会捕获, 其中仅需要少量的加热或冷却。

模拟控制信号精确设置TEC 电流。

MAX1979提供高达6A的单极性输出。

提供斩波稳定的仪表放大器和高精度积分放大器, 以创建比例积分（PI）或比例积分微分（PID）控制器。

仪表放大器可以连接外部NTC或PTC热敏电阻, 热电偶或半导体温度传感器。

提供模拟输出以监控TEC温度和电流。

此外, 单独的过热和欠温输出表明当TEC温度超出范围时。

片上电压基准为热敏电阻桥提供偏置。

MAX1978 / MAX1979采用薄型48引脚薄型QFN-EP 封装, 工作在-40°C至+ 85°C温度范围。

采用外露金属焊盘的耐热增强型QFN-EP封装可最大限度地降低工作结温。

评估套件可用于加速设计。

应用光纤激光模块典型工作电路出现在数据手册的最后。

WDM, DWDM激光二极管温度控制光纤网络设备EDFA光放大器电信光纤接口ATE特征♦尺寸最小, 最安全, 最精确完整的单芯片控制器♦片上功率MOSFET-无外部FET♦电路占用面积<0.93in2♦回路高度<3mm♦温度稳定性为0.001°C♦集成精密积分器和斩波稳定运算放大器♦精确, 独立的加热和冷却电流限制♦通过直接控制TEC电流消除浪涌♦可调节差分TEC电压限制♦低纹波和低噪声设计♦TEC电流监视器♦温度监控器♦过温和欠温警报♦双极性±3A输出电流（MAX1978）♦单极性+ 6A输出电流（MAX1979）订购信息* EP =裸焊盘。

General DescriptionThe MAX6314 low-power CMOS microprocessor (µP)supervisory circuit is designed to monitor power supplies in µP and digital systems. The MAX6314’s RESET output is bidirectional, allowing it to be directly connected to µPs with bidirectional reset inputs, such as the 68HC11. It provides excellent circuit reliability and low cost by eliminating external components and adjustments. The MAX6314 also provides a debounced manual reset input.This device performs a single function: it asserts a reset signal whenever the V CC supply voltage falls below a preset threshold or whenever manual reset is asserted.Reset remains asserted for an internally programmed interval (reset timeout period) after V CC has risen above the reset threshold or manual reset is deasserted.The MAX6314 comes with factory-trimmed reset threshold voltages in 100mV increments from 2.5V to 5V. Preset timeout periods of 1ms, 20ms, 140ms,and 1120ms (minimum) are also available. The device comes in a SOT143 package.F or a µP supervisor with an open-drain reset pin, see the MAX6315 data sheet.________________________ApplicationsComputers ControllersIntelligent InstrumentsCritical µP and µC Power Monitoring Portable/Battery-Powered EquipmentFeatures♦Small SOT143 Package♦RESET Output Simplifies Interface to Bidirectional Reset I/Os♦Precision Factory-Set V CC Reset Thresholds:100mV Increments from 2.5V to 5V♦±1.8% Reset Threshold Accuracy at T A = +25°C ♦±2.5% Reset Threshold Accuracy Over Temp.♦Four Reset Timeout Periods Available: 1ms, 20ms, 140ms, or 1120ms (minimum) ♦Immune to Short V CC Transients ♦5µA Supply Current♦Pin-Compatible with MAX811MAX6314*68HC11/Bidirectional-CompatibleµP Reset Circuit________________________________________________________________Maxim Integrated Products1Pin ConfigurationTypical Operating Circuit19-1090; Rev 2; 12/05Ordering Information continued at end of data sheet.*Patents PendingFor pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Ordering Information†The MAX6314 is available in a SOT143 package, -40°C to+85°C temperature range.††The first two letters in the package top mark identify the part,while the remaining two letters are the lot tracking code.Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing “-T” with “+T” when ordering.M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +2.5V to +5.5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at T A = +25°C.)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Note 1:The MAX6314 monitors V CC through an internal, factory-trimmed voltage divider that programs the nominal reset threshold.Factory-trimmed reset thresholds are available in 100mV increments from 2.5V to 5V (see Ordering and Marking Information ).Note 2:This is the minimum time RESET must be held low by an external pull-down source to set the active pull-up flip-flop.Note 3:Measured from RESET V OL to (0.8 x V CC ), R LOAD = ∞.V CC ........................................................................-0.3V to +6.0V All Other Pins..............................................-0.3V to (V CC + 0.3V)Input Current (V CC ).............................................................20mA Output Current (RESET )......................................................20mA Rate of Rise (V CC )...........................................................100V/µsContinuous Power Dissipation (T A = +70°C)SOT143 (derate 4mW/°C above +70°C).......................320mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +160°C Lead Temperature (soldering, 10sec).............................+300°CMAX631468HC11/Bidirectional-CompatibleµP Reset Circuit_______________________________________________________________________________________3__________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)4.7k Ω PULL-UP 2V/divMAX6314 PULL-UP 2V/divINPUT 5V/div200ns/divPULLUP CHARACTERISTICS100pF4.7k Ω+5V74HC0574HC05V CCGNDMR 100pF+5VRESETMAX63146-50-303090SUPPLY CURRENT vs. TEMPERATURE215TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )-101050347060135SUPPLY CURRENT vs. SUPPLY VOLTAGE215SUPPLY VOLTAGE (V)S U P P L Y C U R R E N T (µA )2344500-50-301090POWER-DOWN RESET DELAYvs. TEMPERATURE1040TEMPERATURE (°C)P O W E R -D O W N R E S E T D E L A Y (µs )-1020303050701.040.96-50-301090NORMALIZED RESET TIMEOUT PERIOD vs. TEMPERATURE (V CC RISING)0.970.981.021.001.03M A X 6314-05TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T P E R I O D -100.991.013050701.0060.994-50-301090NORMALIZED RESET THRESHOLD vs. TEMPERATURE (V CC FALLING)0.9960.9981.0041.000M A X 6314-06TEMPERATURE (°C)N O R M A L I Z E D R E S E T T H R E S H O L D-101.0023050701000101001000MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE20RESET COMP. OVERDRIVE, V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )4060806000-50-301090RESET PULLUP TIME vs. TEMPERATURE100200500300TEMPERATURE (°C)R E S E T P U L L -U P -T I M E (n s )-10400305070Figure 1. Functional Diagram M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit 4_____________________________________________________________________________________________________________________________________________________Pin DescriptionSupply Voltage and Reset Threshold Monitor InputV CC4Manual Reset Input. A logic low on MR asserts reset. Reset remains asserted as long as MR is low, and for the reset timeout period (t RP ) after the reset conditions are terminated. Connect to V CC if not used.MR 3PIN Active-Low Complementary Output. In addition to the normal n-channel pulldown, RESET has a p-channel pullup transistor in parallel with a 4.7k Ωresistor to facilitate connection to µPs with bidirectional resets. See the Reset Output section.RESET2GroundGND 1FUNCTIONNAMEMAX631468HC11/Bidirectional-CompatibleµP Reset Circuit_______________________________________________________________________________________5Detailed DescriptionThe MAX6314 has a reset output consisting of a 4.7k Ωpull-up resistor in parallel with a P-channel transistor and an N-channel pull down (Figure 1), allowing this IC to directly interface with microprocessors (µPs) that have bidirectional reset pins (see the Reset Output section).Reset OutputA µP’s reset input starts the µP in a known state. The MAX6314 asserts reset to prevent code-execution errors during power-up, power-down, or brownout conditions. RESET is guaranteed to be a logic low for V CC > 1V (see the Electrical Characteristics table).Once V CC exceeds the reset threshold, the internal timer keeps reset asserted for the reset timeout period (t RP ); after this interval RESET goes high. If a brownout condition occurs (monitored voltage dips below its pro-grammed reset threshold), RESET goes low. Any time V CC dips below the reset threshold, the internal timer resets to zero and RESET goes low. The internal timer starts when V CC returns above the reset threshold, and RESET remains low for the reset timeout period.The MAX6314’s RESET output is designed to interface with µPs that have bidirectional reset pins, such as the Motorola 68HC11. Like an open-drain output, the MAX6314 allows the µP or other devices to pull RESET low and assert a reset condition. However, unlike a standard open-drain output, it includes the commonly specified 4.7k Ωpullup resistor with a P-channel active pullup in parallel.This configuration allows the MAX6314 to solve a prob-lem associated with µPs that have bidirectional reset pins in systems where several devices connect to RESET . These µPs can often determine if a reset was asserted by an external device (i.e., the supervisor IC)or by the µP itself (due to a watchdog fault, clock error,or other source), and then jump to a vector appropriate for the source of the reset. However, if the µP does assert reset, it does not retain the information, but must determine the cause after the reset has occurred.The following procedure describes how this is done with the Motorola 68HC11. In all cases of reset, the µP pulls RESET low for about four E-clock cycles. It then releases RESET , waits for two E-clock cycles, then checks RESET ’s state. If RESET is still low, the µP con-cludes that the source of the reset was external and,when RESET eventually reaches the high state, jumps to the normal reset vector. In this case, stored state information is erased and processing begins fromscratch. If, on the other hand, RESET is high after the two E-clock cycle delay, the processor knows that it caused the reset itself and can jump to a different vec-tor and use stored state information to determine what caused the reset.The problem occurs with faster µPs; two E-clock cycles is only 500ns at 4MHz. When there are several devices on the reset line, the input capacitance and stray capacitance can prevent RESET from reaching the logic-high state (0.8 x V CC ) in the allowed time if only a passive pullup resistor is used. In this case, all resets will be interpreted as external. The µP is guaranteed to sink only 1.6mA, so the rise time cannot be much reduced by decreasing the recommended 4.7k Ωpullup resistance.The MAX6314 solves this problem by including a pullup transistor in parallel with the recommended 4.7k Ωresis-tor (Figure 1). The pullup resistor holds the output high until RESET is forced low by the µP reset I/O, or by the MAX6314 itself. Once RESET goes below 0.5V, a com-parator sets the transition edge flip-flop, indicating that the next transition for RESET will be low to high. As soon as RESET is released, the 4.7k Ωresistor pulls RESET up toward V CC . When RESET rises above 0.5V,the active p-channel pullup turns on for the 2µs duration of the one-shot. The parallel combination of the 4.7k Ωpullup and the p-channel transistor on-resistance quickly charges stray capacitance on the reset line, allowing RESET to transition low to high with-in the required two E-clock period, even with several devices on the reset line (Figure 2). Once the one-shot times out, the p-channel transistor turns off. This process occurs regardless of whether the reset was caused by V CC dipping below the reset threshold, MR being asserted, or the µP or other device asserting RESET . Because the MAX6314 includes the standard 4.7k Ωpullup resistor, no external pullup resistor is required. To minimize current consumption, the internal pullup resistor is disconnected whenever the MAX6314asserts RESET .Manual Reset InputMany µP-based products require manual reset capabil-ity, allowing the operator, a test technician, or external logic circuitry to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low,and for the reset active timeout period after MR returns high. To minimize current consumption, the internal 4.7k Ωpullup resistor on RESET is disconnected whenever RESET is asserted.M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit 6_______________________________________________________________________________________MR has an internal 63k Ωpullup resistor, so it can be left open if not used. Connect a normally open momen-tary switch from MR to GND to create a manual reset function; external debounce circuitry is not required. If MR is driven from long cables or if the device is used in a noisy environment, connecting a 0.1µF capacitor from MR to ground provides additional noise immunity.__________Applications InformationNegative-Going V CC TransientsIn addition to issuing a reset to the µP during power-up,power-down, and brownout conditions, these devices are relatively immune to short-duration negative-going transients (glitches). The T ypical Operating Character-istics show the Maximum Transient Duration vs. Reset Threshold Overdrive, for which reset pulses are not generated. The graph was produced using negative-going pulses, starting at V RST max and ending below the programmed reset threshold by the magnitude indicated (reset threshold overdrive). The graph shows the maximum pulse width that a negative-going V CC transient may typically have without causing a reset pulse to be issued. As the amplitude of the transient increases (i.e., goes farther below the reset threshold),the maximum allowable pulse width decreases. A 0.1µF bypass capacitor mounted close to V CC provides addi-tional transient immunity.Ensuring a Valid RESET OutputDown to V CC = 0VWhen V CC falls below 1V, RESET no longer sinks current—it becomes an open circuit. Therefore, high-impedance CMOS-logic inputs connected to RESET can drift to undetermined voltages. This presents no problem in most applications, since most µP and other circuitry is inoperative with V CC below 1V. However, in applications where RESET must be valid down to V CC = 0V, adding a pull-down resistor to RESET will cause any stray leakage currents to flow to ground,holding RESET low (Figure 3). R1’s value is not critical;100k Ωis large enough not to load RESET and small enough to pull RESET to ground.Figure 2. MAX6314 Supports Additional Devices on the Reset BusFigure 3. RESET Valid to V CC = Ground CircuitMAX631468HC11/Bidirectional-CompatibleµP Reset Circuit_______________________________________________________________________________________7Figure 4. RESET Timing Diagram†The MAX6314 is available in a SOT143 package, -40°C to +85°C temperature range.††The first two letters in the package top mark identify the part, while the remaining two letters are the lot tracking code.†††Sample stocks generally held on the bolded products; also, the bolded products have 2,500 piece minimum-order quantities.Non-bolded products have 10,000 piece minimum-order quantities. Contact factory for details.Devices are available in both leaded and lead-free packaging. Specify lead-free by replacing “-T” with “+T” when ordering.Note:All devices available in tape-and-reel only. Contact factory for availability.___________________________________________Ordering Information (continued)M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2005 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products, Inc._____________________________Ordering and Marking Information (continued)†The MAX6314 is available in a SOT143 package, -40°C to +85°C temperature range.††The first two letters in the package top mark identify the part, while the remaining two letters are the lot tracking code.†††Sample stocks generally held on the bolded products; also, the bolded products have 2,500 piece minimum-order quantities.Non-bolded products have 10,000 piece minimum-order quantities. Contact factory for details.Devices are available in both leaded and lead-free packaging. Specify lead-free by replacing “-T” with “+T” when ordering.Note:All devices available in tape-and-reel only. Contact factory for availability.Chip InformationTRANSISTOR COUNT: 519Package InformationFor the latest package outline information, go to /packages .。

General DescriptionThe MAX6400–MAX6405 is a family of ultra-low power microprocessor (µP) supervisory circuits used for moni-toring battery, power-supply, and regulated system voltages. Each device contains a precision bandgap reference comparator and is trimmed to specified trip threshold voltages. These devices provide excellent cir-cuit reliability and low cost by eliminating external com-ponents and adjustments when monitoring system voltages from 2.5V to 5.0V. A manual reset input is also included.The MAX6400–MAX6405 assert a reset signal whenev-er the V CC supply voltage falls below a preset thresh-old. These devices are differentiated by their output logic configurations and preset threshold voltages. The MAX6400/MAX6403 (push-pull) and the MAX6402/MAX6405 (open-drain) have an active-low reset (RESET is logic low when V CC is below V TH ). The MAX6401/MAX6404 have an active-high push-pull output (RESET is logic high when V CC is below V TH ). All parts are guaranteed to be in the correct output logic state for V CC down to 1V. The reset circuit is designed to ignore fast transients on V CC . The MAX6400/MAX6401/MAX6402 have voltage thresholds between 2.20V and 3.08V in approximately 100mV increments. The MAX6403/MAX6404/MAX6405 have voltage thresholds between 3.30V and 4.63V in approximately 100mV increments.Ultra-low supply current of 500nA (MAX6400/MAX6401/MAX6402) makes these parts ideal for use in portable equipment. These devices are available in 4-bump chip-scale packages (UCSP™)ApplicationsPortable/Battery-Powered EquipmentCell Phones PDAsMP3 Players Pagers____________________________Featureso Ultra-Small 4-Bump (2 ✕2) Chip-Scale Package,(Package Pending Full Qualification—Expected Completion Date 6/30/01. See UCSP Reliability Section for More Details.)o 70% Smaller Than SC70 Package o Ultra-Low 500nA (typ) Supply Current (MAX6400/MAX6401/MAX6402)o Factory-Trimmed Reset Thresholds from 2.20V to 4.63V in Approximately 100mV Increments o ±2.5% Threshold Accuracy -40°C to +85°C o Factory-Set 100ms (min) Reset Timeout Period o Manual Reset Inputo Guaranteed Reset Valid to V CC = 1.0Vo Three Reset Output Logic Options: Active-Low Push-Pull, Active-High Push-Pull, and Active-Low Open-Drain.o Immune to Short V CC Transients o No External ComponentsMAX6400–MAX6405µP Supervisory Circuits in 4-Bump (2 ✕ 2)Chip-Scale PackageMaxim Integrated Products1Ordering InformationCC thresholds from 2.20V to 4.63V, in approximately 0.1V incre-ments. Choose the desired reset-threshold suffix from Table 1and insert it in the blank space following “S”. There are 21 stan-dard versions with a required order increment of 2500 pieces.Sample stock is generally held on the standard versions only (Table 1). Required order increment is 10,000 pieces for non-standard versions (Table 2). Contact factory for availability. All devices available in tape-and-reel only.UCSP reliability is integrally linked to the user’s assemblymethods, circuit board material, and environment. Refer to the UCSP Reliability Notice in the UCSP Reliability section of this data sheet for more information.Pin Configuration appears at end of data sheet.19-2043; Rev 1; 8/01UCSP is a trademark of Maxim Integrated Products, Inc.For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .M A X 6400–M A X 6405µP Supervisory Circuits in 4-Bump (2 ✕ 2) Chip-Scale Package 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = 1.0V to 5.5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at V CC = 3.0V and T A = +25°C.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC ...........................................................................-0.3V to +6V RESET, RESET (push-pull).........................-0.3V to (V CC + 0.3V)RESET (open-drain)..................................................-0.3V to +6V MR ..............................................................-0.3V to (V CC + 0.3V)Input/Output into Any Pin....................................................20mAContinuous Power Dissipation (T A = +70°C)4-Bump UCSP (derate 3.8mW/°C above +70°C).........303mW Operating Temperature Range ..........................-40°C to +85°C Junction Temperature......................................................+150°C Storage Temperature Range ............................-65°C to +150°C Bump Reflow Temperature .............................................+235°CAll voltages measured with respect to GND, unless otherwise noted.MAX6400–MAX6405µP Supervisory Circuits in 4-Bump (2 ✕ 2)Chip-Scale Package_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)Note 2:Guaranteed by design.M A X 6400–M A X 6405µP Supervisory Circuits in 4-Bump (2 ✕ 2) Chip-Scale Package 4_______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)0.200.60.41.21.00.81.4-40-2020406080SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )50150100200250-40-2020406080POWER-DOWN RESET DELAYvs. TEMPERATURETEMPERATURE (°C)R E S E T D E L A Y (µs )130150140170160200190180210-40-2020406080POWER-UP RESET TIMEOUTvs. TEMPERATUREM A X 6400-05 t o c 03TEMPERATURE (°C)P O W E R -U P R E S E T T I M E O U T (m s)1100010010MAXIMUM TRANSIENT DURATION vs. THRESHOLD OVERDRIVE500200100400300THRESHOLD OVERDRIVE V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )Reset Output A microprocessor’s (µP’s) reset input starts the µP in a known state. These µP supervisory circuits assert reset to prevent code execution errors during power-up, power-down, or brownout conditions.RESET is guaranteed to be a logic low for V CC down to 1V. Once V CC exceeds the reset threshold, an internal timer keeps RESET low for the reset timeout period; after this interval, RESET goes high.If a brownout condition occurs (V CC dips below the reset threshold), RESET goes low. Any time V CC goes below the reset threshold, the internal timer resets to zero, and RESET goes low. The internal timer starts after V CC returns above the reset threshold, and RESET remains low for the reset timeout period.The manual reset input (MR) can also initiate a reset, see the Manual Reset Input section. The MAX6401/ MAX6404 have active-high RESET outputs that are the inverse of the MAX6400/MAX6402/MAX6403/MAX6405 outputs (Figure 1).Manual Reset Input Many µP-based products require manual reset capabil-ity, allowing the operator, a test technician, or external logic circuit to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low, and for the reset active timeout period (t RP) after MR returns high. This input has an internal 50kΩpullup resistor, soit can be left open if it is not used. MR can be drivenwith TTL or CMOS logic levels, or with open-drain/col-lector outputs. Connect a normally open momentary switch from MR to GND to create a manual reset func-tion; external debouncing circuitry is not required. If MRis driven from long cables or if the device is used in anoisy environment, connect a 0.1µF capacitor from MRto ground to provide additional noise immunity (see Figure 1).Applications InformationInterfacing to µP with BidirectionalReset PinsSince the RESET output on the MAX6402/MAX6405 isopen-drain, these devices interface easily with (µPs)that have bidirectional reset pins. Connecting the µP supervisor’s RESET output directly to the microcon-troller’s (µC’s) RESET pin with a single pullup resistor allows either device to assert reset (Figure 2).Negative-Going VCC Transients These devices are relatively immune to short-duration, negative-going V CC transients (glitches).The Typical Operating Characteristics show the Maximum Transient Duration vs. Reset Threshold Overdrive graph, for which reset pulses are not gener-MAX6400–MAX6405µP Supervisory Circuits in 4-Bump (2 ✕ 2)Chip-Scale Package _______________________________________________________________________________________5Pin DescriptionM A X 6400–M A X 6405µP Supervisory Circuits in 4-Bump (2 ✕ 2) Chip-Scale Package 6_______________________________________________________________________________________MAX6400–MAX6405µP Supervisory Circuits in 4-Bump (2 ✕ 2)Chip-Scale Package_______________________________________________________________________________________7Table 1. Factory Trimmed Reset Thresholds**Note: Parts marked with an asterisk (*) are standard versions.Table 2. Device Marking CodesM A X 6400–M A X 6405µP Supervisory Circuits in 4-Bump (2 ✕ 2) Chip-Scale Package 8_______________________________________________________________________________________UCSP ReliabilityThe chip-scale package (UCSP) represents a unique packaging form factor that may not perform equally to a packaged product through traditional mechanical reliabil-ity tests. CSP reliability is integrally linked to the user ’s assembly methods, circuit board material, and usage environment. The user should closely review these areas when considering use of a CSP package. Performance through Operating Life Test and Moisture Resistance remains uncompromised as it is primarily determined by the wafer-fabrication process.tion for a CSP package. CSPs are attached through direct solder contact to the user ’s PC board, foregoing the inherent stress relief of a packaged product lead frame. Solder joint contact integrity must be rmation on Maxim ’s qualification plan, test data, and recommendations are detailed in the UCSP application note, which can be found on Maxim ’s website at .Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600______________________9©2001 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.Package InformationµP Supervisory Circuits in 4-Bump (2 ✕ 2)Chip-Scale PackageMAX6400–MAX6405。

高频信号发生器_______________概述MAX038是一种只需极少外围电路就能实现高 频、高精度输出三角波、锯齿波、正弦波、方波 和脉冲波的精密高频函数发生器芯片。

内部提供 的2.5V 基准电压和一个外接电阻和电容可以控制 输出频率范围在0.1Hz 到20MHz 。

占空比可在较大 的范围内由一个±2.3V的线性信号控制变化，便 于进行脉冲宽度调制和产生锯齿波。

频率调整和 频率扫描可以用同样的方式实现。

占空比和频率 控制是独立的。

通过设置2个TTL 逻辑地址引脚合适的逻辑电 平，能设定正弦波，方波或三角波的输出。

所有 波形的输出都是峰-峰值为±2VP -P 的信号。

低阻 抗输出能力可以达到±20mA。

____________________________性能o 频率调节范围：0.1Hz 到20MHzo 三角波, 锯齿波, 正弦波, 方波和脉冲波 o 频率和占空比独立可调 o 频率扫描范围：350：1 o 可控占空比：15%到85% o 低阻抗输出缓冲器： 0.1Ω o 低失真正弦波： 0.75% o 低温度漂移： 200ppm/°C______________型号信息TTL 逻辑地址引脚SYNC 从内部振荡器输出占 空比固定为50%的信号，不受其它波占空比的影 响，从而同步系统中其它振荡器。

内部振荡器 允许被连接着相位检波器输入端（PDI ）的外部 TTL 时钟同步。

型号 MAX038CPP MAX038CWP MAX038C/D MAX038EPP MAX038EWP工作温度 0°C 到 +70°C 0°C 到 +70°C 0°C 到 +70°C -40°C 到 +85°C -40°C 到 +85°C引脚--封装 20 Plastic DIP 20 SO Dice* 20 Plastic DIP 20 SO.__________________应用精密函数信号发生器 压控振荡器 频率调制器*Contact factory for dice specifications.__________________引脚图脉宽调制器 锁相环 频率合成器FSK 发生器（正弦波和方波）________________________________________________________________ Maxim Integrated Products1For free samples & the latest literature: , or phone 1-800-998-8800. For small orders, phone 408-737-7600 ext. 3468MAX038高频信号发生器图1. 内部结构及基本工作电路_______________ 详细说明MAX038是一种高频函数信号发生器，它可以使 用最少的外部元件而产生低失真正弦波，三角波， 锯齿波，方波（脉冲波）。

XC61CN替换MAX6377和MAX6380及MAX6808例：XC61CN 替换MAX6377XC61CN 替换MAX6380XC61CN 替换MAX6808系列名称：【XC61CN/XC61CC】特点：低功耗(0.8V)输入电压(V)：最小--0.8V；最大--6V输出电压(V)：最小--0.7V；最大--10V最大输出电流(mA)：400mA消耗电流(μA)：0.7A封装：SOT-23，SOT-89，SSOT-24，TO-92【TOREX-XC61CN系列】描述：1.XC61CN系列是一款高精度,低功耗的电压检测器芯片,并采用了CMOS生产工艺和激光微调技术。

2.XC61CN系列受温度漂移特性的影响很小,电压检测精度很高。

3.XC61CN系列有CMOS和N沟道开漏两种输出模式供选择。

【TOREX-XC61CN系列】特点：●高精度：±2%, ±1% (VDF=2.6V~5.1V)●低消耗电流：0.7μA(TYP.)[VIN=1.5V]●检测电压范围：能够在0.8V～6.0V范围内以0.1V间隔设定●工作电压范围：0.7V～6.0V(低检测电压0.8V～1.5V), 0.7V～10.0V(一般检测电压1.6V～6.0V)●检测电压温度特性：±100ppm/℃(TYP.)●輸出形式：N沟道开漏/CMOS輸出●封装：SSOT-24, SOT-23, SOT-89, TO-92TOREX日本IC均可完全替代下列型号:XC6221Bxx2MR 替代MIC5253 XC6115xxxxMR 替代LTC699CN8 XC6221BXX2MR 替代MIC5255-xxBM5 XC6116x0xxMR 替代LTC2915xxS8 XC6221BXX2MR 替代MIC5259 XC6121 替代MAX6320XC6204Bxx2DR 替代MIC5305-xxYML XC6122 替代MAX6320XC6419 替代MIC5371 XC6123 替代MAX6320XB1086 替代MIC39100-xxBS XC6124 替代MAX6320XC6205 替代MIC5203 XC6113 替代MAX823XC6411 替代MIC5371 XC6103 替代MAX823XC6412 替代MIC5371 XC6112 替代MAX823XC6415 替代MIC5371 XC6102 替代MAX823XCM406 替代MIC5264 XC6115 替代MAX824XC8101 替代MIC94060 XC6105 替代MAX824XC6601 替代MCP1727 XC6114xxxxMR 替代DS1819BRXC6213 替代TC1014-xxVCT713 XC6104xxxxMR 替代DS1819BRXC6212 替代TC1014-xxVCT713 XC61H 替代MAX809/803XC62KNxx02PR 替代TC59xx02EMBTR XC6101xxxxMR 替代DS1819ARXC62KNxx02MR 替代TC59xx02ECB XC6106xxxxER 替代MAX6335XC62EPxxxxMR 替代TC57xx02ECT XC6106xxxxER 替代MAX6402XC6206Pxx2TB替代TC55RPxx02EZB XC6107 替代MAX825XC6206Pxx2PR 替代TC55RPxx02EMB XC6116xxxxER 替代MAX6402XC6206Pxx2MR 替代TC55RPxx01ECB XC612 替代MAX6779XC6203Pxx2FR 替代TC1264-xxVDB XC61CNxx02NR 替代MAX6377XRxx XC6207 替代TC1014-xxVCT713 XC61CNxx02NR 替代MAX6380XRxx XC6217 替代TC1014-xxVCT XC61CNxx02MR 替代MAX6808URxx XC6206Pxx2PR 替代MCP1700T-xx02E/TT XC61FC 替代MAX809XC6209Bxx2MR 替代TC1014-xxVCT713 XC61FC2912MR 替代MAX809SEUR XC6209Bxx2MR 替代TC1015xxVCT XC61CCxx02NR 替代MAX6375XRxx XC6209Bxx2MR 替代TC1185xxVCT XC61CCxx02NR 替代MAX6378XRxx XC6203Pxx2FR 替代TC1262-xxVDB XC61CCxx02MR 替代MAX6806URxx XC6204Bxx2MR 替代LX8211-xxISE XC6111xxxxMR 替代DS1819ARXC6215Pxx2NR 替代MC78LC00 XC6101 替代MAX823XC6210Bxx2 替代MC78M00 XC6111 替代MAX823XC6401CHxxMR 替代LP3988IMX-xx XC6104 替代MAX824XC6403DHxxMR 替代LP3988IMF-xx XC6114 替代MAX824XC6210B122DR 替代LP3990TL-xx XC6106 替代MAX825XC6210B122DR 替代LP3990MF-xx XC6116 替代MAX825XC6221A182MR 替代LP3990MF-xx XC6107xxxxMR 替代MAX6337USxxD3 XC6202Pxx2TH 替代LM2931AZxx XC6117xxxxMR 替代MAX6337USxxD3 XC6214 替代LM1117MPX-xx XC6107xxxxMR 替代MAX6841/2XC6419 替代LP5996 XC6117xxxxMR 替代MAX6841/2XC6411 替代LP5996 XC61FNxxx2MR 替代MAX803XC6412 替代LP5996 XC61CNxx02MR 替代MAX6380URXC6415 替代LP5996 XC61CCxx02MR 替代MAX6375URXB1086Pxx1JR 替代LM1086CS XC6117 替代MAX825XB1117K12BFR 替代LM1117S XC6106 替代MIC2775XB1117PxxxFR 替代LM1117MPX-xx XC6116 替代MIC2775XC6203Pxx2FR 替代LM1117MPX-xx XC612 替代MIC2777XC6202Pxx2TH 替代LM2936Z-xx XCM410 替代MIC2774XB1117Pxx1FR 替代LM340S XC61CCxx02PR 替代TC54VCxx02EMB XC6202Pxx2TH 替代LM340LAZ-xx XC61CCxx02TB 替代TC54VCxx02EZB XC6202Pxx2MR 替代LM3480IM3-xx XC61H 替代TCM809XC6203P332FR 替代LM3940IMP-3.3 XCM410 替代TC52XC6202Pxx2TH 替代LM78LxxACZ XC6120 替代TC54XC6404DHxxMR 替代LMS5258MF-xx XC612 替代TC52XC6202Pxx2MR 替代LP2950 XC61CNxx02MR 替代TC53Nxx02ECTTR XC6204Bxx2MR 替代LP2978 XC61CNxx02NR 替代TC53Nxx02EVCTR XC6204Bxx2MR 替代LP2980AIM5-xx XC61CN 替代TC54VNXC6204Bxx2MR 替代LP2980IM5-xx XC6202Pxx2TH 替代L4931ABZxxXC6204Axx2MR 替代LP2980IM5X-xx XC6202Pxx2TH 替代L4931CZxxXC6204Bxx2MR 替代LP2981AIM5-xx XC6202Pxx2PR 替代L78LxxABUTRXC6204Bxx2MR 替代LP2981IM5-xx XC6202Pxx2TH 替代L78LxxABZXC6204Bxx2MR 替代LP2982AIM5-xx XC6202Pxx2PR 替代L78LxxACUXC6204Bxx2MR 替代LP2982IM5-xx XC6202Pxx2TH 替代L78LxxACZXC6204Bxx2MR 替代LP2985AIM5-xx XC6202Pxx2TH 替代L78LxxCZXC6204Bxx2MR 替代LP2985IM5-xx XC6203Pxx2FR 替代LD1117SXC6204Bxx2MR 替代LP3984IBP-xx XC6204Bxx2MR 替代LD2979MxxXC6403 替代LP3982 XC6202Pxx2TH 替代LD2979ZxxXC6204Bxx2DR 替代LP3985IBL-xx XC6204Bxx2MR 替代LD2980ABMxxXC6204Bxx2MR 替代LP3985IM5-x.x XC6201Pxx2PR 替代LD2980ABUxxTR XC62H 替代NCP584HSNxxT1G XC6204Bxx2MR 替代LD2980ACMxxXC62E 替代NCP584HSNxxT1G XC6201Pxx2PR 替代LD2980ACUxxXC6404 替代NCP400FCT2G XC6204Bxx2MR 替代LD2981ABMxxXB1086 替代LM317MBDTRK XC6201Pxx2PR 替代LD2981ABUxxXC6202 series 替代LM2931CD XC6204Bxx2MR 替代LD2981ACMxxXC6202Pxx2TH 替代LM2931Z-xx XC6201Pxx2PR 替代LD2981ACUxxXC6202Pxx2MR 替代LP2950 XC6202Pxx2TH 替代LExxABZ/CZXC6202Pxx2TH 替代LP2950CZ-xx XC6401 替代NCP583XVxxT2G XB1086 替代MC33269DTRK XC6214 替代MC78LCxxHT1XC6203Pxx2FR 替代MC33275ST-xxT3 XC6219 替代NCP584HSNxxT1G XC6204Bxx2MR 替代MC33761 XC6219Bxx2MR 替代BAxxxLBSGXC6206Pxx2PR 替代MC78FCxxHT1 XC6219 替代BA0xxLBSGXC6203xxx2PR 替代MC78LCxxHT1 XC6206Pxx2TB 替代RE5RExxACXC6202Pxx2TH 替代MC78LxxACP/BCP XC6206Pxx2PR 替代RH5RLxxAAXC6204Bxx2MR 替代MC78PCxxNTR XC6206Pxx2TH 替代RE5RLxxAAXC6206Pxx2PR 替代MC78RCxxHT1 XC6206Pxx2TB 替代RE5RLxxACXC6217Axx2MR 替代NCP584HSNxxT1G XC62EPxx02MR 替代RN5RGxxAATR XC6203Pxx2FR 替代SC5201-1GSTR3 XC62H 替代RN5RGxxAATR XC6402 替代NCP400FCT2G XC6419 替代R5325XC6403/04 替代NCP400FCT2G XB1086 替代RN5RGxxAATR XC6405 替代NCP400FCT2G XC6411 替代R5325XC6204Bxx2MR 替代R1111Nxx1A/B XC6412 替代R5325XC6204Bxx2MR 替代R1112Nxx1A/B XC6415 替代R5325XC6204Bxx2MR 替代R1112Nxx1B-TR XC8101 替代R5520HXC6206Pxx2PR 替代RH5RExxAA XC6204Bxx2MR 替代R1110Nxx1A/BXC6206Pxx2TH 替代RE5RExxAA。

General DescriptionThe MAX6365–MAX6368 supervisory circuits simplify power-supply monitoring, battery-backup control func-tions, and memory write protection in microprocessor (µP) systems. The circuits significantly improve the size,accuracy, and reliability of modern systems with an ultra-small integrated solution.These devices perform four basic system functions:1) Provide a µP reset output during V CC supply power-up, power-down, and brownout conditions.2) Internally control V CC to backup-battery switching tomaintain data or low-power operation for CMOS RAM, CMOS µPs, real-time clocks, and other digital logic when the main supply fails.3) Provide memory write protection through internalchip-enable gating during supply or processor faults.4) Include one of the following options: a manual resetinput (MAX6365), a watchdog timer function (MAX6366), a battery-on output (MAX6367), or an auxiliary user-adjustable reset input (MAX6368).The MAX6365–MAX6368 operate from V CC supply volt-ages as low as 1.2V. The factory preset reset threshold voltages range from 2.32V to 4.63V (see the Ordering Information ). In addition, each part is offered in three reset output versions: push-pull active low, open-drain active low, or open-drain active high (see the Selector Guide ). The MAX6365–MAX6368 are available in minia-ture 8-pin SOT23 packages.ApplicationsCritical µP/µC Power Portable/Battery-Monitoring Powered Equipment Fax Machines Set-Top Boxes Industrial Control POS EquipmentComputers/ControllersFeatures♦Low +1.2V Operating Supply Voltage (V CC or V BATT )♦Precision Monitoring of +5.0V, +3.3V, +3.0V, and +2.5V Power-Supply Voltages♦On-Board Gating of Chip-Enable Signals, 1.5ns Propagation Delay♦Debounced Manual Reset Input (MAX6365)♦Watchdog Timer, 1.6s Timeout (MAX6366)♦Battery-On Output Indicator (MAX6367)♦Auxiliary User-Adjustable RESET IN (MAX6368)♦Low 10µA Quiescent Supply Current ♦Three Available Output StructuresPush-Pull RESET Open-Drain RESET Open-Drain RESET♦RESET/RESET Valid Down to 1.2V Guaranteed (V CC or V BATT )♦Power-Supply Transient Immunity ♦150ms min Reset Timeout Period ♦Miniature 8-Pin SOT23 PackageMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating________________________________________________________________Maxim Integrated Products1Pin Configurations19-1658; Rev 3; 12/05For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Ordering Information*These parts offer a choice of reset threshold voltages. From the Reset Threshold Ranges table, insert the desired threshold volt-age code in the blank to complete the part number. SOT parts come in tape-and-reel only and must be ordered in 2500-piece increments. See Device Marking Codes for a complete parts list,including SOT top marks and standard threshold versions. See Selector Guide for a listing of device features.Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing “-T” with “+T” when ordering.Typical Operating Circuit appears at end of data sheet.M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable GatingABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V = +2.4V to +5.5V, V = +3.0V, CE IN = V , reset not asserted, T = -40°C to +85°C. Typical values are at T = +25°C,Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Terminal Voltages (with respect to GND)V CC , BATT, OUT.......................................................-0.3V to +6V RESET (open drain), RESET (open drain)................-0.3V to +6V BATT ON, RESET (push-pull), RESET IN,WDI, CE IN, CE OUT...........................-0.3V to (V OUT + 0.3V)MR ..............................................................-0.3V to (V CC + 0.3V)Input CurrentV CC Peak ..............................................................................1A V CC Continuous.............................................................250mA BATT Peak.....................................................................250mA BATT Continuous.............................................................40mAGND...............................................................................75mA Output CurrentOUT...............................Short-Circuit Protected for up to 10s RESET, RESET , BATT ON, CE OUT...............................20mA Continuous Power Dissipation (T A = +70°C)8-Pin SOT23 (derate 8.75mW/°C above +70°C)........700mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Junction Temperature .....................................................+150°C Lead Temperature (soldering, 10s).................................+300°CMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V CC = +2.4V to +5.5V, V BATT = +3.0V, CE IN = V CC , reset not asserted, T A = -40°C to +85°C. Typical values are at T A = +25°C,M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 4_______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)8109121115141316-400-2020406080SUPPLY CURRENTvs. TEMPERATURE (NO LOAD)TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )0.20.60.40.81.01.2BATTERY SUPPLY CURRENT (BACKUP MODE) vs. TEMPERATURETEMPERATURE (°C)B A T T E R Y S U P P L YC U R R E N T (µA )-402040-200608021437658-40-2020406080BATT-TO-OUT ON-RESISTANCEvs. TEMPERATURETEMPERATURE (°C)B A T T -T O -O U T O N -R E S I S T A NC E (Ω)ELECTRICAL CHARACTERISTICS (continued)(V= +2.4V to +5.5V, V = +3.0V, CE IN = V , reset not asserted, T = -40°C to +85°C. Typical values are at T = +25°C,Note 2:V BATT can be 0 anytime, or V CC can go down to 0 if V BATT is active (except at startup).Note 3:RESET is pulled up to OUT. Specifications apply for OUT = V CC or OUT = BATT.Note 4:The chip-enable resistance is tested with V CC = V TH(MAX)and CE IN = V CC / 2.MAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________5Typical Operating Characteristics (continued)(T A = +25°C, unless otherwise noted.)00.40.20.80.61.21.01.4-4020-20406080V CC TO OUT ON-RESISTANCEvs. TEMPERATURETEMPERATURE (°C)V C C T O O U T O N -R E S I S T A N C E (Ω)190195205200210RESET TIMEOUT PERIOD vs. TEMPERATUREM A X 6365/8-05TEMPERATURE (°C)R E S E T T I M E O U T P E R I O D (m s )-402040-206080301575604513512010590TEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-402040-206080V CC TO RESET PROPAGATION DELAYvs. TEMPERATURE2.03.02.55.04.54.03.5RESET THRESHOLD vs. TEMPERATURETEMPERATURE (°C)T H R E S H O L D (V )-402040-206080110010100010,000MAXIMUM TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVERESET THRESHOLD OVERDRIVE V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )40030035025020005015010003215498761000.5 1.0 1.5 2.0 2.5 3.03.5BATTERY SUPPLY CURRENT vs. SUPPLY VOLTAGEV CC (V)B A T T E R Y S U P P L YC U R R E N T (µA )M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 6_______________________________________________________________________________________1.2341.2351.236MAX6368RESET IN THRESHOLD vs. TEMPERATUREM A X 6365/8 -10TEMPERATURE (°C)V R T H (V )-402040-2060801.01.91.61.32.82.52.2MAX6368RESET IN TO RESET PROPAGATION DELAYvs. TEMPERATURETEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-402040-206080013245C LOAD (pF)P R O P A G A T I O N D E L A Y (n s )10050150200CHIP-ENABLE PROPAGATION DELAY vs. CE OUT LOAD CAPACITANCE515102025-40-2020406080TEMPERATURE (°C)C E I N T O C E O U T O N -R E S I S T A N C E (Ω)CE IN TO CE OUT ON-RESISTANCEvs. TEMPERATURE1.01.31.21.11.51.41.91.81.71.62.0-40-2020406080TEMPERATURE (°C)W A T C H D O G T I M E O U T P E R I O D (s )MAX6366WATCHDOG TIMEOUT PERIODvs. TEMPERATURETypical Operating Characteristics (continued)(T A = +25°C, unless otherwise noted.)MAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________7M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 8_______________________________________________________________________________________Detailed DescriptionThe Typical Operating Circuit shows a typical connec-tion for the MAX6365–MAX6368. OUT powers the static random-access memory (SRAM). If V CC is greater than the reset threshold (V TH ), or if V CC is lower than V TH but higher than V BATT , V CC is connected to OUT. If V CC is lower than V TH and V CC is less than V BATT ,BATT is connected to OUT. OUT supplies up to 150mA from V CC . In battery-backup mode, an internal MOSFET connects the backup battery to OUT. The on-resistance of the MOSFET is a function of backup-battery voltage and is shown in the BATT-to-OUT On-Resistance vs.Temperature graph in the T ypical Operating Char-acteristics .Chip-Enable Signal GatingThe MAX6365–MAX6368 provide internal gating of CE signals to prevent erroneous data from being written toCMOS RAM in the event of a power failure. During nor-mal operation, the CE gate is enabled and passes all CE transitions. When reset asserts, this path becomes disabled, preventing erroneous data from corrupting the CMOS RAM. All of these devices use a series trans-mission gate from CE IN to CE OUT. The 2ns propaga-tion delay from CE IN to CE OUT allows the devices to be used with most µPs and high-speed DSPs.During normal operation, CE IN is connected to CE OUT through a low on-resistance transmission gate.This is valid when reset is not asserted. If CE IN is high when reset is asserted, CE OUT remains high regard-less of any subsequent transitions on CE IN during the reset event.If CE IN is low when reset is asserted, CE OUT is held low for 12µs to allow completion of the read/write oper-ation (F igure 1). After the 12µs delay expires, the CEFunctional DiagramMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________9OUT goes high and stays high regardless of any sub-sequent transitions on CE IN during the reset event.When CE OUT is disconnected from CE IN, CE OUT is actively pulled up to OUT.The propagation delay through the chip-enable circuit-ry depends on both the source impedance of the drive to CE IN and the capacitive loading at CE OUT. The chip-enable propagation delay is production tested from the 50% point of CE IN to the 50% point of CE OUT, using a 50Ωdriver and 50pF load capacitance.Minimize the capacitive load at CE OUT to minimize propagation delay, and use a low-output-impedance driver.Backup-Battery SwitchoverIn a brownout or power failure, it may be necessary to preserve the contents of the RAM. With a backup bat-tery installed at BATT, the MAX6365–MAX6368 auto-matically switch the RAM to backup power when V CC falls. The MAX6367 has a BATT ON output that goes high in battery-backup mode. These devices require two conditions before switching to battery-backup mode:1) V CC must be below the reset threshold.2) V CC must be below V BATT .Table 1 lists the status of the inputs and outputs in bat-tery-backup mode. The devices do not power up if the only voltage source is on BATT. OUT only powers upfrom V CC at startup.Many µP-based products require manual reset capabili-ty, allowing the user or external logic circuitry to initiate a reset. For the MAX6365, a logic low on MR asserts reset.Reset remains asserted while MR is low and for a mini-mum of 150ms (t RP ) after it returns high. MR has an inter-nal 20k Ωpullup resistor to V CC . This input can be driven with TTL/CMOS logic levels or with open-drain/collector outputs. Connect a normally open momentary switch from MR to GND to create a manual reset function; exter-nal debounce circuitry is not required. If MR is driven from long cables or the device is used in a noisy environ-ment, connect a 0.1µF capacitor from MR to GND to pro-vide additional noise immunity.Figure 1. Reset and Chip-Enable TimingM A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 10______________________________________________________________________________________Watchdog Input (MAX6366 Only)The watchdog monitors µP activity through the watch-dog input (WDI). If the µP becomes inactive, reset asserts. To use the watchdog function, connect WDI to a bus line or µP I/O line. A change of state (high to low,low to high, or a minimum 100ns pulse) resets the watchdog timer. If WDI remains high or low for longer than the watchdog timeout period (t WD ), the internal watchdog timer runs out and a reset pulse is triggered for the reset timeout period (t RP ). The internal watchdog timer clears whenever reset asserts or whenever WDI sees a rising or falling edge. If WDI remains in either a high or low state, a reset pulse asserts periodically after every t WD (Figure 2).BATT ON Indicator (MAX6367 Only)BATT ON is a push-pull output that drives high when in battery-backup mode. BATT ON typically sinks 3.2mA at 0.1V saturation voltage. In battery-backup mode, this terminal sources approximately 10µA from OUT. Use BATT ON to indicate battery-switchover status or to supply base drive to an external pass transistor for higher current applications (Figure 3).RESET IN Comparator (MAX6368 Only)RESET IN is compared to an internal 1.235V reference.If the voltage at RESET IN is less than 1.235V, reset asserts. Use the RESET IN comparator as an undervolt-age detector to signal a failing power supply or as a secondary power-supply reset monitor.To program the reset threshold (V RTH ) of the secondary power supply, use the following (see Typical Operating Circuit ):V RTH = V REF (R1 / R2 + 1)where V REF = 1.235V. To simplify the resistor selection,choose a value for R2 and calculate R1:R1 = R2 [(V RTH / V REF ) - 1]Since the input current at RESET IN is 25nA (max),large values (up to 1M Ω) can be used for R2 with no significant loss in accuracy. For example, in the Typical Operating Circuit , the MAX6368 monitors two supply voltages. To monitor the secondary 5V logic or analog supply with a 4.60V nominal programmed reset thresh-old, choose R2 = 100k Ω, and calculate R1 = 273k Ω.Reset OutputA µP’s reset input starts the µP in a known state. The MAX6365–MAX6368 µP supervisory circuits assert a reset to prevent code-execution errors during power-up, power-down, and brownout conditions. RESET is guaranteed to be a logic low or logic high, depending on the device chosen (see the Ordering Information ).RESET or RESET asserts when V CC is below the reset threshold and for at least 150ms (t RP ) after V CC rises above the reset threshold. RESET or RESET also asserts when MR is low (MAX6365) and when RESET IN is less than 1.235V (MAX6368). The MAX6366 watch-dog function will cause RESET (or RESET ) to assert in pulses following a watchdog timeout (Figure 2).Applications InformationOperation Withouta Backup Power SourceThe MAX6365–MAX6368 provide battery-backup func-tions. If a backup power source is not used, connect BATT to GND and OUT to V CC .Watchdog Software ConsiderationsOne way to help the watchdog timer monitor the soft-ware execution more closely is to set and reset the watchdog at different points in the program rather than pulsing the watchdog input periodically. F igure 4shows a flow diagram in which the I/O driving theFigure 2. MAX6366 Watchdog Timeout Period and Reset Active TimeMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating______________________________________________________________________________________11watchdog is set low in the beginning of the program,set high at the beginning of every subroutine or loop,and set low again when the program returns to the beginning. If the program should hang in any subrou-tine, the problem would be quickly corrected.Replacing the Backup BatteryWhen V CC is above V TH , the backup power source can be removed without danger of triggering a reset pulse.The device does not enter battery-backup mode when V CC stays above the reset threshold voltage.Negative-Going V CC TransientsThese supervisors are relatively immune to short-dura-tion, negative-going V CC transients. Resetting the µP when V CC experiences only small glitches is usually not desirable.The T ypical Operating Characteristics section has a Maximum Transient Duration vs. Reset Threshold Overdrive graph for which reset is not asserted. The graph was produced using negative-going V CC pulses,starting at V CC and ending below the reset threshold by the magnitude indicated (reset threshold overdrive).The graph shows the maximum pulse width that a neg-ative-going V CC transient can typically have without triggering a reset pulse. As the amplitude of the tran-sient increases (i.e., goes further below the reset threshold), the maximum allowable pulse width decreases. Typically, a V CC transient that goes 100mV below the reset threshold and lasts for 30µs will not trig-ger a reset pulse.A 0.1µF bypass capacitor mounted close to the V CC pin provides additional transient immunity.M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 12______________________________________________________________________________________standard versions only. Contact factory for availability of nonstandard versions.MAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating______________________________________________________________________________________13Pin Configurations (continued)M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 14______________________________________________________________________________________Typical Operating CircuitChip InformationTRANSISTOR COUNT: 729PROCESS: CMOSSOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable GatingMAX6365–MAX6368Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________15©2005 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products, Inc.Package Information(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to /packages .)。