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UCC1946资料

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UCC1946UCC2946UCC3946

SLUS247B - FEBRUARY 2000FEATURES•Fully Programmable Reset Threshold•Fully Programmable Reset Period•Fully Programmable Watchdog Period•2% Accurate Reset Threshold•VDDCan Go as Low as 2V•18µA MaximumIDD•Reset Valid Down to 1VMicroprocessor Supervisor with Watchdog Timer

67WDIWP8VDD3RES

5POWERTO

CIRCUITRY

A3A2A1A0CLKCLR8-BITCOUNTER

400nAWDO1GNDEDGEDETECTWATCHDOGTIMING100mV1.235V2RTH4RP1.235V.

400nAPOWERONRESETBLOCK DIAGRAM

Note:Pinoutrepresents the 8-pinTSSOPpackage.UDG-98001DESCRIPTIONTheUCC3946isdesignedtoprovideaccuratemicroprocessorsupervi-sion,includingresetandwatchdogfunctions.Duringpowerup,theICassertsaresetsignalRESwithVDDaslowas1V.Theresetsignalre-mainsasserteduntiltheVDDvoltagerisesandremainsabovethere-setthresholdfortheresetperiod.Bothresetthresholdandresetperiodareprogrammablebytheuser.TheICisalsoresistanttoglitchesontheVDDline.OnceREShasbeendeasserted,anydropsbelowthethresholdvoltageneedtobeofcertaintimedurationandvoltagemag-nitudetogeneratearesetsignal.ThesevaluesareshowninFigure1.AnI/Olineofthemicroprocessormaybetiedtothewatchdoginput(WDI)forwatchdogfunctions.IftheI/Olineisnottoggledwithinasetwatchdogperiod,programmablebytheuser,WDOwillbeasserted.The watchdog function will be disabled during reset conditions.TheUCC3946isavailablein8-pinSOIC(D),8-pinDIP(NorJ)and8-pinTSSOP(PW) packages to optimize board space.元器件交易网www.cecb2b.comUCC1946UCC2946UCC3946

ELECTRICAL CHARACTERISTICS:Unless otherwise specified,VDD= 2.1V to 5.5V for UCC1946 and UCC2946;VDD= 2V to 5.5V for UCC3946; TA = 0°C to 70°C for UCC3946, –40°C to 95°C for UCC2946, and –55°C to 125°C for UCC1946;TA=TJPARAMETERSTEST CONDITIONSMINTYPMAXMINTYPMAXUNITSUCC3946UCC1946 & UCC2946Operating Voltage2.05.52.15.5VSupply Current10181218µAMinimumVDD(Note 1)11.1VReset SectionReset ThresholdVDDRising1.2101.2351.2601.1701.2351.260VThresholdHysteresis1515mVInput Leakage55nA

Output High VoltageISOURCE= 2mAVDD–0.3VDD–0.3VOutput Low VoltageISINK= 2mA0.10.1VVDD= 1V,ISINK= 20uA0.20.4VVDDto Output DelayVDD= -1mV/µs (Note 2)120120µsReset PeriodCRP= 64nF160200260140200320msWatchdog SectionWDIInput High0.7·VDD0.7·VDDVWDIInput Low0.3·VDD0.3·VDDVWatchdog PeriodCWP= 64nF1.121.602.080.961.602.56sWatchdog Pulse Width5050nsOutput High VoltageISOURCE= 2mAVDD–0.3VDD–0.3VOutput Low VoltageISINK= 2mA0.10.1VNote 1:This is the minimum supply voltage whereRESis considered valid.Note 2:Guaranteed by design.Not 100% tested in production.ABSOLUTE MAXIMUM RATINGSVIN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10VStorage Temperature. . . . . . . . . . . . . . . . . . .–65°C to +150°CJunction Temperature. . . . . . . . . . . . . . . . . . .–55°C to +150°CLead Temperature (Soldering, 10 sec.). . . . . . . . . . . . .+300°CCurrentsarepositiveinto,negativeoutofthespecifiedterminal.ConsultPackagingSectionoftheDatabookforthermallimita-tions and considerations of packages.WPWDIVDDWDO12348765RTHGNDRESRPSOIC-8,TSSOP-8,DIL-8(Top View)D,PW,N or J PackageCONNECTION DIAGRAM元器件交易网www.cecb2b.comUCC1946UCC2946UCC3946

TheUCC3946supervisorycircuitprovidesaccuratere-setandwatchdogfunctionsforavarietyofmicroproces-sorapplications.Theresetcircuitpreventsthemicroprocessorfromexecutingcodeduringundervoltageconditions,typicallyduringpower-upandpower-down.Inordertopreventerraticoperationinthepresenceofnoise,voltage“glitches”whosevoltageamplitudeandtimedurationarelessthanthevaluesspecifiedinFig.1are ignored.Thewatchdogcircuitmonitorsthemicroprocessor’sac-tivity,ifthemicroprocessordoesnottoggleWDIduringtheprogrammablewatchdogperiodWDOwillgolow,alertingthemicroprocessor’sinterruptofafault.TheWDOpinistypicallyconnectedtothenon-maskablein-putofthemicroprocessorsothatanerrorrecoveryrou-tine can be executed.APPLICATION INFORMATION

020406080100120140160180200

100110120130

140150160170180DELAY(µS)OVERDRIVEVOLTAGEWITHRESPECTTORESETTHRESHOLD(mV)RTSENSESGLITCH,RESGOESLOWFORRESETPERIODGLITCHESAREIGNORED,RESBREMAINSHIGHFigure 1.Overdrive voltage vs.delay to output lowonRESB.Slew rate:–1V/mS;monitored voltage =VDD.GND:Ground reference for the IC.RES:ThispinishighonlyifthevoltageontheRTHhasrisenabove1.235V.OnceRTHrisesabovethethreshold,thispinremainslowfortheresetperiod.ThispinwillalsogolowandremainlowiftheRTHvoltagedipsbelow1.235V for an amount of time determined by Figure 1.RTH:Thisinputcomparesitsvoltagetoaninternal1.25Vreference.Byusingexternalresistors,ausercanpro-gram any reset threshold he wishes to achieve.RP:Thispinallowstheusertoprogramtheresetperiodby adjusting an external capacitor.VDD:Supply voltage for the IC.WDI:Thispinistheinputtothewatchdogtimer.Ifthispinisnottoggledorstrobedwithinthewatchdogperiod,WDOis asserted.WDO:Thispinisthewatchdogoutput.ThispinwillbeassertedlowiftheWDIpinisnotstrobedortoggledwithin the watchdog period.WP:Thispinallowstheusertoprogramthewatchdogperiod by adjusting an external capacitor.PIN DESCRIPTIONS

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UCC38C43P中文资料

UCC38C43P中文资料

UCC38C43P中文资料

双极CMOS低功耗电流模式PWM控制器

特点：

相对UC3842A家族来说增加了引脚对引脚兼容功能；

1MHZ工作频率；

50uA待机电流，最大100uA；

在52KHZ时，低运作电流2.3mA；

快速35ns周期过流限制；

1A的峰值输出电流;

轨到轨输出摆幅 25ns上升、20ns下降时间；

1%初始2.5V误差放大器参考电压；

微调的振荡器放电电流；

欠压锁定新版本；

体积小MSOP-8包装；

运用：

开关模式电源；

DC-DC转换器；

板安装功率模块；

描述：

UCC38C4x 家庭是一个高性能的电流模式 PWM 控制器。这是一个增强的 BiCMOS 与引脚对引脚兼容版本的行业标准 UC384xA家庭和家庭的 PWM 控制器 UC384x。此外，7 伏特低电压启动版本提供作为 UCC38C40 和 UCC38C41。

提供必要的功能，以控制固定频率，峰值电流模式电源，该系列提供以下的性能优势。该器

件提供高频率运行高达 1 低启动和工作电流兆赫，从而减少启动损耗和低操作功率消耗提高效率。该器件还具有 35 ns 的快速电流检测至输出延迟时间和峰值输出± 1 改进的上升和下降的直接驱动外部 MOSFET 大时代潮流的能力。

UCC38C4x家庭提供8引脚封装 MSOP (DGK), SOIC (D) and PDIP (P).

原理框图

建议工作条件：

最小 最大 单位

输入电压，Vdd 18 V

输出电压.Vout 18 V

平均输出电流 ,Iout 200 mA

基准输出电流,Iout(ref) -20 mA

操作结点温度，Tj -55 150 oC

在操作free-air温度绝对最大额定值（除非有其他说明）

电源电压 (VDD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 V

UCC28019 中文资料

UCC28019 中文资料

UCC28019内部结构如图1-2所示。

图1-2 UCC28019内部结构图

UCC28019具体功能介绍如下：

（1） 系统保护

系统的保护使系统工作在安全工作范围内，系统保护主要包括软启动、Vcc欠压锁定(UVLO)、输人掉电保护(IBOP)、输出过压保护(OVP)、开环保护/待机模式(OLP/Standby)、输出欠压检测(UVD)/增强动态响应(EDR)、过流保护、软过流(SOC)、峰值电流限制(PCL)等。

（2） 栅极驱动

栅极驱动输出具有电流最优化结构，可以以很高的开关速度直接驱动大容量MOSFET的栅极。内部的钳位电压将MOS-FET栅极上的电压钳位于12. 5V，外部所接的栅极驱动电阻RGATE限制了栅极驱动电路寄生电感和寄生电容的上升时间和阻尼振荡。通常在MOSFET栅极附近用一个lOkΩ的电阻对地连接，消除栅极杂散电容，防止无意的 dv/dt触发开通。

（3） 电流环 系统电流环包括电流平均放大、脉宽调制(PWM)、外部升压电感和外部电流传感电阻等环节。从电流传感电阻检测到的负极性信号送人ISENSE引脚进行缓冲、反相放大后，得到的正极性信号通过电流放大器（gmi）进行平均，其输出即为ICOMP引脚，ICOMP引脚上的电压与平均电感电流成比例，该引脚对地(GND)外接一电容提供电流环路补偿并可对纹波电流进行滤波。平均放大器的增益由VCOMP引脚内部的电压决定，该增益设置为非线性，因此可以适应全球范围内的交流输人电压。无论芯片处于故障模式还是待机模式，ICOMP引脚均在内部接至4V电平。

脉宽调(PWM)电路将ICOMP引脚电压信号与周期性的斜坡信号比较，产生上升沿调制的输出信号，如果斜坡电压信号大于ICOMP引脚电压，则PWM输出为高电平，斜坡的斜率是内部VCOMP引脚电压的非线性函数。

由内部时钟触发的PWM输出信号在周期开始时为低电平，该电平会持续一小段时间，称之为最小关断时间(toff(min))，而后，斜坡电压信号线性上升，与ICOMP电压交叉，斜坡电压与ICOMP电压的交叉点决定了关断时间(toff)，也即Doff，由于Doff满足Boost拓扑结构的Dote=VIN/VOUT，而且输人VIN是正弦电压, ICOMP与电感电流成比例，控制环路会迫使电感电流跟随输人电压呈现正弦波形以进行Boost调制，因此平均输人电流也呈现正弦波形。

UCC1804中文资料

UCC1804中文资料

UCC1800/1/2/3/4/5

UCC2800/1/2/3/4/5

UCC3800/1/2/3/4/5

SLUS270C-MARCH1999-REVISEDJANUARY2005FEATURES

•100µATypicalStartingSupplyCurrent

•500µATypicalOperatingSupplyCurrent

•Operationto1MHz

•InternalSoftStart

•InternalFaultSoftStart

•InternalLeading-EdgeBlankingoftheCurrentSenseSignal

•1AmpTotem-PoleOutput

•70nsTypicalResponsefromCurrent-SensetoGateDriveOutput

•1.5%ToleranceVoltageReference

•SamePinoutasUC3842andUC3842ADESCRIPTION

TheUCC1800/1/2/3/4/5familyofhigh-speed,low-powerintegratedcir-

cuitscontainallofthecontrolanddrivecomponentsrequiredforoff-line

andDC-to-DCfixedfrequencycurrent-modeswitchingpowersupplies

withminimalpartscount.

ThesedeviceshavethesamepinconfigurationastheUC1842/3/4/5

family,andalsooffertheaddedfeaturesofinternalfull-cyclesoftstart

andinternalleading-edgeblankingofthecurrent-senseinput.

TheUCC1800/1/2/3/4/5familyoffersavarietyofpackageoptions,tem-

UCC1810中文资料

UCC1810中文资料

UCC1810

UCC2810

UCC3810

02/99FEATURES

•Single Oscillator Synchronizes TwoPWMs

•150A Startup Supply Current

•2mA Operating Supply Current

•Operation to 1MHz

•Internal Soft Start

•Full-Cycle Fault Restart

•Internal Leading Edge Blanking of theCurrent Sense Signal

•1 Amp Totem Pole Outputs

•75ns Typical Response from CurrentSense to Output

•1.5% Tolerance Voltage ReferenceDESCRIPTION

TheUCC3810isahigh-speedBiCMOSintegratedcircuitwhichimple-

mentstwosynchronizedpulsewidthmodulatorsforuseinoff-lineand

DC-to-DC power supplies.

TheUCC3810providesperfectsynchronizationbetweentwoPWMsbyus-

ingthesameoscillator.Theoscillator’ssawtoothwaveformcanbeusedfor

slope compensation if required.

Usingatoggleflipfloptoalternatebetweenmodulators,theUCC3810en-

suresthatonePWMwillnotslave,interfere,orotherwiseaffecttheother

PWM.ThistoggleflipflopalsoensuresthateachPWMwillbelimitedto