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MAX4837EUT28BD1-T中文资料

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General DescriptionThe MAX4836/MAX4837 family of low-dropout (LDO)linear regulators feature an accurate current-limiting switch with an integrated FLAG or RESET function. These devices operate from 2.5V to 5.5V and deliver up to 500mA of load current at a preset output voltage. Preset output voltage levels are 1.8V/2.5V/2.8V/3.0V/3.3V.The MAX4836/MAX4837 offer a programmable soft-start control function to eliminate false reset during startup. The MAX4836 provides a FLAG function to noti-fy the system when the load current exceeds the limit.The MAX4837 provides a RESET function to notify the system when the output drops below the threshold.Additionally, reverse-current protection prevents cur-rent flowing from the output to the input. Other features include a low 90µA quiescent current, a 0.1µA shut-down current.The MAX4836/MAX4837 are available in space-saving 6-pin SOT23 and TDFN packages. Each device is speci-fied over the -40°C to +85°C extended temperature range. Contact factory for other programmed output volt-age versions from 1.5V to 3.3V in 100mV increments.For pin-compatible 100mA versions of this device, refer to the MAX4832/MAX4833. For pin-compatible 250mA versions of this device, refer to the MAX4834/MAX4835.ApplicationsSDIO Ports and Devices Notebook Computers USB Ports and Devices Cell Phones PDAs and Palmtop DevicesGPS SystemsFeatures♦Guaranteed Minimum 500mA Load Current♦Accurate Current Limit♦Preset Output Voltages: 1.8V/2.5V/2.8V/3.0V/3.3V ♦2.5V to 5.5V Supply Voltage Range ♦Adjustable Soft-Start ♦Low Dropout Voltage ♦Thermal Shutdown♦Reverse-Current Protection♦Shutdown Output Discharge (MAX4837)♦Low 90µA Supply Current♦Ultra-Low 0.1µA Shutdown Current ♦FLAG and Latch Off (MAX4836) or RESET (MAX4837)♦Tiny SOT23 and TDFN (3mm x 3mm) PackagesMAX4836/MAX4837500mA LDO Linear Regulators withCurrent-Limiting Switch________________________________________________________________Maxim Integrated Products1Ordering Information19-3374; Rev 0; 7/04For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Note:“xy” are placeholders for the output voltage levels of the devices. Insert the values found in Table 1 at the end of this doc-ument in the place of “xy”. The “_” is a placeholder for either the RESET or the FLAG feature. Insert “B” in the place of “_” for RESET and “C” for FLAG . “dd” is a placeholder for the reset timeout period. Insert the values found in Table 2 in the place of “dd.” For example, MAX4837EUT18BD2 has a 1.8V output volt-age, RESET feature, and a 30ms reset timeout period. Note that “dd” applies only to the devices with RESET option and does not apply to the devices with FLAG option. For devices with the FLAG option, leave dd blank. Standard versions require a mini-mum order increment of 2.5k units. Nonstandard versions must be ordered in 10k unit increments. Contact factory for availability.*Future product—contact factory for availability.Pin ConfigurationsTables 1 and 2 and Selector Gui de appear at end of data sheet.M A X 4836/M A X 4837500mA LDO Linear Regulators with Current-Limiting SwitchABSOLUTE 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.IN, SHDN , FLAG , OUT to GND ................................-0.3V to +6V RESET to GND .........................................-0.3V to (V OUT + 0.3V)SS to GND ...................................................-0.3V to (V IN + 0.3V)IN to OUT...............................................................................±6V OUT Short Circuit to GND..........................................Continuous All Pins ESD Handling (Human Body Model).........................2kVContinuous Power Dissipation (T A = +70°C)6-Pin SOT23 (derate 9.1mW/°C above +70°C)................727mW 6-Pin TDFN (derate 24.4mW/°C above +70°C)..........1951.2mW Operating Temperature Range ...........................-40°C to +85°C Operating Junction Temperature Range...........-40°C to +125°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX4836/MAX4837500mA LDO Linear Regulators withCurrent-Limiting Switch_______________________________________________________________________________________3Note 2:The dropout voltage is measured from V IN to V OUT when V OUT is 2% below its nominal value. The nominal output voltage ismeasured from V OUT to GND when V IN is 1V greater than V OUT . Defined only for V OUT ≥2.5V.Note 3:Soft-start time is defined as the time required for the output to rise from 10% of its nominal value to 90% of its nominal value.Note 4:For V OUT < 2V, V IN must be above 2.5V.Note 5:This is the maximum time OUT can be out of tolerance before a reset is issued. It is implemented to ensure that momentaryoutput glitches do not trigger a reset condition.Note 6:In startup mode, the blanking time counter is not started until the soft-start time has elapsed. The total time from startup toFLAG issued is t SS + t BLANK .ELECTRICAL CHARACTERISTICS (continued)M A X 4836/M A X 4837500mA LDO Linear Regulators with Current-Limiting Switch 4_______________________________________________________________________________________Typical Operating Characteristics(V IN = V OUT + 1V, SHDN = IN, C OUT = 3.3µF, T A = +25°C, unless otherwise noted.)QUIESCENT CURRENT vs. INPUT VOLTAGE(NO LOAD)V IN (V)I Q (µA )5432120406080100120006QUIESCENT CURRENT vs. INPUT VOLTAGE(500mA LOAD)V IN (V)I Q (µA )5432161002003004005006007008000MAXIMUM TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVERESET THRESHOLD OVERDRIVE (mV)P U L S E D U R A T I O N (µs )1015304560759001100DROPOUT VOLTAGE vs. LOAD CURRENTLOAD CURRENT (mA)D R O P O U T V O L T A GE (m V )40030020010030609012015018000500POWER-SUPPLY REJECTION RATIOvs. FREQUENCYFREQUENCY (kHz)P S R R (d B )1010.1-70-60-50-40-30-20-100-800.01100REGION OF STABLE C OUT ESRvs. LOAD CURRENTLOAD CURRENT (mA)C O U T E S R (Ω)1234567450400350300250200150100500500OUTPUT NOISE vs. FREQUENCYFREQUENCY (Hz)O U T P U T N O I S E (µV R M S )10k1k 1001020304050010100kSOFT-START RESPONSE (C SS = FLOATING)V SS 1V/divV OUT 2V/div V IN 2V/div2ms/divt SS_______________________________________________________________________________________5MAX4836/MAX4837500mA LDO Linear Regulators withCurrent-Limiting SwitchSOFT-START RESPONSE(C SS = 0.01µF)V SS 1V/divV OUT 2V/divV IN 2V/div2ms/divt SSSOFT-START RESPONSE(C SS = 0.1µF)V IN 2V/divV SS 1V/divV OUT 2V/div20ms/divt SSLOAD-TRANSIENT RESPONSEV OUT 50mV/div AC-COUPLED100µs/divV IN = 4.3V V OUT = 3.3V C IN = 0.1µF C OUT = 3.3µFI LOAD : STEP FROM 10mA TO 100mA BACK TO 10mALOAD-TRANSIENT RESPONSENEAR DROPOUTV OUT 50mV/div AC-COUPLED100µs/divV IN = 3.4V V OUT = 3.3V C IN = 0.1µF C OUT = 3.3µFI LOAD : STEP FROM 10mA TO 100mA BACK TO 10mALINE-TRANSIENT RESPONSEV OUT 50mV/div AC-COUPLED100µs/divC IN = 0.1µF C OUT = 3.3µF V OUT = 3.3V I LOAD = 10mA5V V IN500mV/div 4.5V RESET RESPONSE TO V INV RESET 2V/divV OUT 2V/divV IN 2V/div40ms/divt RESETC SS = FLOATINGRESET RESPONSE TO V OUTV RESET 1V/divV OUT 1V/div40ms/div t RESETV IN = 3.5V, C SS = FLOATINGRESET RESPONSE TO SHUTDOWNV RESET 2V/divV OUT 2V/divV SHDN 2V/div40ms/divt RESETV IN = 3.5V, C SS = FLOATINGTypical Operating Characteristics (continued)(V IN = V OUT + 1V, SHDN = IN, C OUT = 3.3µF, T A = +25°C, unless otherwise noted.)M A X 4836/M A X 4837500mA LDO Linear Regulators with Current-Limiting Switch 6_______________________________________________________________________________________Typical Operating Characteristics (continued)(V IN = V OUT + 1V, SHDN = IN, C OUT = 3.3µF, T A = +25°C, unless otherwise noted.)FLAG RESPONSE WHEN OUT IS SHORTED TO GND < BLANKING TIMEMAX4836 toc17V OUT 2V/div1ms/divI OUT200mA/divV FLAG 5V/divFLAG RESPONSE WHEN OUT IS SHORTED TO GND > BLANKING TIME(IN IS TOGGLED)V OUT 1V/div 10ms/divV IN 2V/divV 2V/divFLAG CONNECTED TO LOGIC SUPPLYt BLANKSTARTUP IN AN OVERLOAD CONDITION(C SS NOT CONNECTED)V SS 1V/divV 2V/div V OUT 2V/div2ms/divt BLANKV IN 2V/divt SSV OUT = 2.5VI LOAD = I LIMIT MAXIMUMFLAG CONNECTED TO LOGIC SUPPLYSTARTUP IN AN OVERLOAD CONDITION(C SS = 0.01µF)V SS 1V/divV 2V/divV OUT 2V/div4ms/divt BLANKV IN 2V/divt SSV OUT = 2.5VI LOAD = I LIMIT MAXIMUMFLAG CONNECTED TO LOGIC SUPPLYNORMALIZED OUTPUT VOLTAGEvs. TEMPERATURETEMPERATURE (°C)N O R M A L I Z E D O U T P U T V O L T A G E 603510-150.9960.9981.0001.0021.0040.994-4085FLAG RESPONSE WHEN OUT IS SHORTED TO GND > BLANKING TIME(SHDN IS TOGGLED)V OUT 1V/div 10ms/divV 2V/divV 2V/divFLAG CONNECTED TO LOGIC SUPPLYt BLANKDetailed Description The MAX4836/MAX4837 are ultra-low quiescent current, low-dropout linear regulators with an integrated current limiter. These devices guarantee up to 500mA drive capabilities and regulate the preset output voltage.The MAX4836 has a flag output that asserts low when the load current exceeds the current limit for more than the blanking time (t BLANK). The MAX4837 has a reset output that asserts low when the regulator output volt-age is below the reset threshold voltage (V RESET). V RESET is 87.5% of the nominal output voltage. Figure 1 shows the simplified functional diagram and Figure 2 shows the typical application circuits.FLAG Output (MAX4836) The open-drain FLAG output goes low and the LDO’s pass transistor is latched off when the current in the pass transistor is at its output current limit for more than the blanking time (t BLANK). Cycling IN or SHDN(high to low to high) brings the device out of its latched-off state and back into normal operation.RESET Output (MAX4837)The RESET output asserts when one of the following conditions occurs:•The input voltage (V IN) is below the input undervolt-age lockout threshold (V UVLO).•The output voltage (V OUT) is below the reset thresh-old (V RESET).•SHDN is pulled low.•The device is in thermal shutdown.•When V OUT> V IN.RESET remains low for the reset timeout period (t RESET)after reset conditions are terminated. There are four RESET timeout periods available as shown in the Electrical Characteristics table. RESET is available in apush-pull configuration as shown in the Selector Guide.ShutdownPull SHDN low to shut down the LDO and reduce the quiescent current consumption of the device from 90µAto 0.1µA. In shutdown mode, the pass transistor, con-trol circuit, and reference circuit are turned off. Connect SHDN to a supply voltage greater than V IH to turn onthe LDO.MAX4836/MAX4837500mA LDO Linear Regulators withCurrent-Limiting Switch _______________________________________________________________________________________7M A X 4836/M A X 4837500mA LDO Linear Regulators with Current-Limiting Switch 8_______________________________________________________________________________________Figure 2. Typical Application CircuitsShutdown Discharge (MAX4837) OUT discharges through a 900Ωinternal resistor during shutdown mode.Reverse OUT to IN Current When the output voltage is greater than the input volt-age, the internal pass transistor turns off. To avoid reverse-charging the input source, the current at IN is guaranteed to be below 3µA when V OUT≥V IN.Current Limit The MAX4836/MAX4837 include an accurate internal current-limiting circuit. OUT can be shorted to ground indefinitely without damaging the part.The MAX4836 latches off if the load current exceeds the current limit for more than the blanking time (see the FLAG Output section). During soft-start, the device does not latch off to an overload condition. During an overload condition, the MAX4837 holds the current at current limit until the thermal limit is reached. Once the junction tem-perature reaches +165°C, thermal shutdown occurs.Thermal Shutdown When the junction temperature (T J) exceeds +165°C, the LDO’s pass transistor turns off allowing the junction to cool. The LDO’s pass transistor turns on again after the IC’s junction temperature cools by 15°C, resulting in a pulsed output during continuous thermal-overload conditions.Soft-Start During power-up, the soft-start ensures that the output ramps up slowly reducing inrush current peaks. See the soft-start response time plots in the Typical Operating Characteristics. The soft-start time (t SS) is given by the following equation:t SS= C SS(ms)where C SS is in nF.A soft-start capacitor (C SS) of 10nF gives a 10ms t SS. A 1ms minimum soft-start time is fixed internally to ensure that the output rises slowly even without any external capacitor at SS pin to ground. The device is in soft-start mode when either the voltage at IN or SHDN is cycled high to low to high.Applications InformationCapacitor Selection and RegulatorStabilityFor stable operation over the full temperature range andwith load currents up to 500mA, use a 3.3µF (min) ceramic output capacitor with an ESR <0.2Ω. To reducenoise and improve load transient response, stability, and power-supply rejection, use larger output capacitor values such as 10µF (note that some ceramic capacitors exhibit large capacitance and ESR variation with temper-ature). X7R capacitors provide good performance overthe -40°C to +85°C operating temperature range.To improve power-supply rejection and transient response, use a 0.1µF capacitor between IN and GND.The MAX4836/MAX4837 remain stable with purely resistive loads or current loads up to 500mA.15kV Operational ESD ProtectionA 3.3µF or higher value ceramic capacitor from OUT toGND provides a 15kV (Human Body Model) protectionat OUT. The ESR value of the capacitor should be lessthan 0.2Ω.Reset Transient ImmunityThe reset circuit is relatively immune to short duration,falling V OUT transients. The Typical Operating Characteristics show a graph of the Maximum Transient Duration vs. Reset Threshold Overdrive for which reset isnot asserted. The graph was produced using falling V OUT transients starting at V OUT and ending below the reset threshold by the magnitude indicated (reset threshold overdrive). The graph shows the maximum pulse widththat a falling V OUT transient can typically have without triggering the reset pulse. As the amplitude of the tran-sient increases (i.e., goes further below the reset thresh-old), the maximum allowable pulse width decreases. Typically, a V OUT transient that goes only 10mV below thereset threshold and lasts up to 54µs does not trigger areset pulse.LayoutWhen using the TDFN package, connect its exposed paddle to G ND to provide a low thermal resistancepath for heat transfer from the IC junction to the printedcircuit board.MAX4836/MAX4837500mA LDO Linear Regulators withCurrent-Limiting Switch _______________________________________________________________________________________9M A X 4836/M A X 4837500mA LDO Linear Regulators with Current-Limiting Switch 10______________________________________________________________________________________Table 1. Standard Output Voltage Suffix 100mV increments. Contact factory for availability.Table 2. R E S E T Timeout Period SuffixPin Configurations (continued)Chip InformationTRANSISTOR COUNT: 1575PROCESS: BiCMOSTDFN Exposed Pad: Connected to GNDMAX4836/MAX4837500mA LDO Linear Regulators withCurrent-Limiting SwitchPackage 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 .)M A X 4836/M A X 4837500mA LDO Linear Regulators with Current-Limiting Switchimplied. 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©2004 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to /packages .)。

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MAX31785中文资料

MAX31785中文资料

_________________________________________________________________Maxim Integrated Products __1本文是英文数据资料的译文，文中可能存在翻译上的不准确或错误。

如需进一步确认，请在您的设计中参考英文资料。

有关价格、供货及订购信息，请联络Maxim 亚洲销售中心：10800 852 1249 (北中国区)，10800 152 1249 (南中国区)，或访问Maxim 的中文网站： 。

6通道智能风扇控制器MAX3178519-5703; Rev 0; 12/10+表示无铅(Pb)/符合RoHS 标准的封装。

T = 卷带包装。

*EP = 裸焊盘。

概述MAX31785是一款闭环多通道风扇控制器。

自动闭环风扇控制架构将风扇控制在尽可能低的转速，从而节省系统功率。

低风扇转速的其它优势包括：有效降低可闻噪声和更长的风扇寿命、更少的系统维护。

根据用户可编程查找表(LUT)，器件根据11个温度传感器中的一个或多个传感器测量值，自动调节6个独立风扇的转速。

也可以由外部主机手动控制风扇转速，器件自动调整风扇转速。

器件具有风扇状况诊断功能，帮助用户预防将要发生的风扇故障。

器件还可监测多达6路远端电压。

应用网络交换机/路由器基站服务器智能电网系统工业控制定购信息特性S 6路独立的风扇控制通道 支持3线和4线风扇 自动闭环风扇转速控制 基于RPM 或PWM 控制 可选手动控制模式快速、慢速PWM 频率选项 风扇交替启动，缓解电源压力 双转速计(支持12个风扇) 风扇故障检测 风扇运转状态监测 非易失风扇运转时间表S 支持多达11个温度传感器6个外部温度二极管，带有串联电阻自动抵消功能 1个内部温度传感器 4个I 2C 数字温度传感器对所有温度传感器进行故障检测S 6路ADC 测量远端电压S PMBus™兼容命令接口S I 2C/SMBus™兼容串行总线，带有总线超时功能S 板载非易失故障记录和默认配置设置S 无需外部时钟S +3.3V 供电PMBus 是SMIF, Inc.的商标。

MEMORY存储芯片MAX488EESA+T中文规格书

MEMORY存储芯片MAX488EESA+T中文规格书

±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers__________Function Tables (MAX481E/MAX483E/MAX485E/MAX487E/MAX1487E) Table 1. Transmitting Table 2. Receiving__________Applications Information The MAX481E/MAX483E/MAX485E/MAX487E–MAX491E and MAX1487E are low-power transceivers for RS-485 and RS-422 communications. These “E” versions of the MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 provide extra protection against ESD. The rugged MAX481E, MAX483E, MAX485E, MAX497E–MAX491E, and MAX1487E are intended for harsh envi-ronments where high-speed communication is important. These devices eliminate the need for transient suppres-sor diodes and the associated high capacitance loading. The standard (non-“E”) MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 are recommended for applications where cost is critical.The MAX481E, MAX485E, MAX490E, MAX491E, and MAX1487E can transmit and receive at data rates up to 2.5Mbps, while the MAX483E, MAX487E, MAX488E, and MAX489E are specified for data rates up to 250kbps. The MAX488E–MAX491E are full-duplex transceivers, while the MAX481E, MAX483E, MAX487E, and MAX1487E are half-duplex. In addition, driver-enable (DE) and receiver-enable (RE) pins are included on the MAX481E, MAX483E, MAX485E, MAX487E, MAX489E, MAX491E, and MAX1487E. When disabled, the driver and receiver outputs are high impedance.±15kV ESD Protection As with all Maxim devices, ESD-protection structures are incorporated on all pins to protect against electro-static discharges encountered during handling and assembly. The driver outputs and receiver inputs have extra protection against static electricity. Maxim’s engi-neers developed state-of-the-art structures to protect these pins against ESD of ±15kV without damage. The ESD structures withstand high ESD in all states: normal operation, shutdown, and powered down. After an ESD event, Maxim’s MAX481E, MAX483E, MAX485E, MAX487E–MAX491E, and MAX1487E keep working without latchup.ESD protection can be tested in various ways; the transmitter outputs and receiver inputs of this product family are characterized for protection to ±15kV using the Human Body Model.Other ESD test methodologies include IEC10004-2 con-tact discharge and IEC1000-4-2 air-gap discharge (for-merly IEC801-2).ESD Test Conditions ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test set-up, test methodology, and test results.Human Body Model F igure 4 shows the Human Body Model, and F igure 5 shows the current waveform it generates when dis-charged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of inter-est, which is then discharged into the test device through a 1.5kΩresistor.IEC1000-4-2 The IEC1000-4-2 standard covers ESD testing and per-formance of finished equipment; it does not specifically refer to integrated circuits (Figure 6).MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E Maxim Integrated9±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversThe major difference between tests done using the Human Body Model and IEC1000-4-2 is higher peak current in IEC1000-4-2, because series resistance is lower in the IEC1000-4-2 model. Hence, the ESD with-stand voltage measured to IEC1000-4-2 is generally lower than that measured using the Human Body Model. Figure 7 shows the current waveform for the 8kV IEC1000-4-2 ESD contact-discharge test.The air-gap test involves approaching the device with a charged probe. The contact-discharge method connects the probe to the device before the probe is energized.Machine Model The Machine Model for ESD tests all pins using a 200pF storage capacitor and zero discharge resis-tance. Its objective is to emulate the stress caused by contact that occurs with handling and assembly during manufacturing. Of course, all pins require this protec-tion during manufacturing—not just inputs and outputs. Therefore,after PC board assembly,the Machine Model is less relevant to I/O ports.MAX487E/MAX1487E:128 Transceivers on the Bus The 48kΩ, 1/4-unit-load receiver input impedance of the MAX487E and MAX1487E allows up to 128 transceivers on a bus, compared to the 1-unit load (12kΩinput impedance) of standard RS-485 drivers (32 transceivers maximum). Any combination of MAX487E/MAX1487E and other RS-485 transceivers with a total of 32 unit loads or less can be put on the bus. The MAX481E, MAX483E, MAX485E, and MAX488E–MAX491E have standard 12kΩreceiver input impedance.MAX483E/MAX487E/MAX488E/MAX489E:Reduced EMI and Reflections The MAX483E and MAX487E–MAX489E are slew-rate limited, minimizing EMI and reducing reflections caused by improperly terminated cables. F igure 16 shows the driver output waveform and its Fourier analy-sis of a 150kHz signal transmitted by a MAX481E, MAX485E, MAX490E, MAX491E, or MAX1487E. High-frequency harmonics with large amplitudes are evident.F igure 17 shows the same information displayed for a MAX483E, MAX487E, MAX488E, or MAX489E transmit-ting under the same conditions. F igure 17’s high-fre-quency harmonics have much lower amplitudes, and the potential for EMI is significantly reduced.Low-Power Shutdown Mode(MAX481E/MAX483E/MAX487E) A low-power shutdown mode is initiated by bringing both RE high and DE low. The devices will not shut down unless both the driver and receiver are disabled. In shutdown, the devices typically draw only 0.5µA of supply current.RE and DE may be driven simultaneously; the parts are guaranteed not to enter shutdown if RE is high and DE is low for less than 50ns. If the inputs are in this state for at least 600ns, the parts are guaranteed to enter shutdown.F or the MAX481E, MAX483E, and MAX487E, the t ZH and t ZL enable times assume the part was not in the low-power shutdown state (the MAX485E, MAX488E–MAX491E, and MAX1487E can not be shut down). The t ZH(SHDN)and t ZL(SHDN)enable times assume the parts were shut down (see Electrical Characteristics).Figure 16. Driver Output Waveform and FFT Plot of MAX485E/MAX490E/MAX491E/MAX1487E Transmitting a 150kHz SignalFigure 17. Driver Output Waveform and FFT Plot ofMAX483E/MAX487E–MAX489E Transmitting a 150kHz SignalMAX481E/MAX483E/MAX485E/ MAX487E–MAX491E/MAX1487E 12。

比较常用的笔记本芯片内部管脚解释

比较常用的笔记本芯片内部管脚解释

比较常用的笔记本芯片内部管脚解释统供电芯片型号有:一、美信产的用的最多的两个芯片MAX1632、MAX1635可以互换,它们的工作原理一样。

主要产生出3.3V、5V 、12V电压。

二、MAX1631、MAX1634、MAX1904这三种芯片的工作原理与MAX1632 MAX1635差不多，但不能与MAX1632MAX1635芯片互换。

说明:1、MAX1631、MAX1634、MAX1904互相可以代换。

2、MAX1631、1634、1904没有12V输出,这一点与MAX1632、1635不一样,如果MAX1631、1634、1904的板子上需要12V的话,一般是在5V输出的后级,电路中设计一个升压电路。

(参考升压电路一节)3、MAX1632、1635芯片上的12#、 3#的反馈信号脚没有使用,但MAX1631、1634、1904还使用了这个反馈角。

4、4#、5#的定义与MAX1632、1635不一样。

三、MAX785 MAX786用于东芝的笔记本电脑PⅡPⅢ较多。

四、LTC1628用于索尼、康柏的笔记本较多。

五、系统供电电路维修方法与经验小结:1、23#有总控制SHDN时? 9#2.5V不正常或9#为0V时 ?芯片坏或者18#、25# 5V供激放供电没有查D1与D22、7# 28#应有5V高电平控制信号，有时为NQ送来，有时与21#相连，由21#5V电压作为控制信号用，还有的由键盘芯片送来。

注:7#与28#加上一个5V的控制信号，电路应该有正常3.3V或5V电压输出，如果还没有，一般是芯片损坏。

3、先不加电测对地阻值，首先测高端管是否击穿，供电负载是否击穿，如果是OΩ表明击穿短路了，如果有正常的几百欧阻值，但一加电就短路，表明是稳压二极管已经保护了，这是高端还管击穿的结果。

4、电源控制器芯片本身损坏的故障现象:①供电和控制都正常，但没有输出。

②待机状态下总供电正常，但一按开机键总供电瞬间短路。

5、除负载短路原因外，芯片任何一脚无电压输出为芯片损坏(在供电输入与控制都正常情况下)。

MAX1873数据手册的中文翻译

MAX1873数据手册的中文翻译

简单的限流开关模式Li +电池充电控制器--------------------------------------------------------------------------概述低成本的MAX1873R/S/T提供所有功能需要对高达4A或以上的2 - ，3 - 或4 - 系列的锂离子电池进行简单而有效的充电。

它提供调节充电电流和电压，少于±0.75％时，总电压在电池端出现错误。

在降压的DC - DC配置下，外部P沟道MOSFET有效地为电池充电，这是低成本的设计。

MAX1873R/S/T使用两个控制回路调节电池电压和充电电流，一起工作的两个控制回路在电压和电流调节之间顺利转换。

一个额外的控制回路限制电流来自输入端，可以使AC适配器尺寸和成本最小化。

模拟电压还提供其输出正比于充电电流，以便ADC或微控制器可以监控充电电流。

在多化学充电器设计时，MAX1873也可能被用来作一个有效的有限电流源对镍镉或镍氢电池充电。

MAX1873R/S/T采用节省空间的16引脚QSOP封装是可用的。

使用评估板（MAX1873EVKIT），可以帮助减少设计时间。

--------------------------------------------------------------------------应用笔记本电脑便携式网络片2 - ，3 - ，或4节锂离子电池充电器6 - ，9 – 10节镍电池充电器手持式仪表便携式桌面助理（PDA）台式插座充电器引脚配置在数据资料的最后。

--------------------------------------------------------------------------特征•低成本和简单电路•可对2 - ，3 - ，或4节串联锂离子电池充电•AC适配器输入电流限制回路•还可对以镍为主的电池充电•模拟输出监视充电电流•± 0.75％的电池调节电压•5μA关断电池电流•输入电压高达28V•200mV的压差电压/100％占空比•可调充电电流•为300kHz的PWM振荡器降低了噪音•采用节省空间的16引脚QSOP•采用MAX1873评估板以加快设计----------------------------------------------------------------------订购信息部分温度 .范围 PIN的封装MAX1873REEE -40 °C至85 °C 16 QSOPMAX1873SEEE-40 °C至85 °C16 QSOPMAX1873TEEE-40 °C至85 °C16 QSOP------------------------------------------------------------------典型工作电路极限值CSSP，CSSN，DCIN接GND ·······················- 0.3V至30V VL，ICHG / EN接GND ························- 0.3V至6V VH，EXT接DCIN ····························- 6V至0.3V VH，EXT接GND ·······················( V DCIN 0.3V） - 0.3V EXT接VH ······························6V至- 0.3V DCIN接VL······························30V至- 0.3V VADJ，REF，CCI，CCV，CCS， IOUT接GND··············- 0.3V至（VL 0.3V）BATT，CSB接GND···························- 0.3V至20V CSSP接CSSN·····························- 0.3V至0.6V CSB接BATT·····························- 0.3V至0.6V VL源电流··································+50mA VH反向电流································+40mA 连续功耗（TA=70℃）16引脚QSOP封装（在70° C以上，功率衰减8.3mW/° C···········+667mW 工作温度范围MAX1873_EEE·····················-40°C至+85°C 结点温度································+150 °C 存储温度范围··························-65°C至+150°C 引线温度（焊接，10S)···························300°C 超出“绝对最大额定值”中所列的压力可能会造成设备的永久性损坏。