2024年2月25日发(作者：刀醉易)

元器件交易网19-2531; Rev 0; 10/02Low-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsGeneral DescriptionFeaturesThe MAX6736–MAX6745 are low-power dual-/triple-voltage microprocessor (µP) supervisors. TheseoDual-/Triple-Supply Reset Voltage Monitorsdevices assert a reset if any monitored supply fallsoPrecision Factory-Set Reset Thresholds forbelow its factory-trimmed or adjustable threshold andMonitoring from 0.9V to 5.0Vmaintain reset for a minimum timeout period after alloAdjustable Reset Input Down to 0.488Vsupplies rise above their thresholds. The integratedo150ms and 1200ms (min) Reset Timeout Perioddual/triple supervisory circuits significantly reduce sizeOptionsand power compared to separate ICs or discrete com-ponents. The low supply current of 6µA makes theseoVCC1 Power-OK Output for Power-Supplydevices ideal for portable cing Applications (MAX6741/MAX6744)The MAX6736/MAX6737 are dual fixed-voltage µPoPower-Fail Input/Power-Fail Outputsupervisors with a manual reset input. The MAX6738/(MAX6742/MAX6745)MAX6739 have one fixed and one adjustable reseto6µA Supply Currentthreshold and a manual reset input. The MAX6740/oTiny SC70 PackageMAX6743 are triple-voltage µP supervisors with twofixed and one user-adjustable reset threshold ng InformationThe MAX6741/MAX6744 are dual-voltage µP supervi-sors with a power-OK (POK) output ideal for power-PARTTEMP RANGEPIN-PACKAGEsupply sequencing. The MAX6742/MAX6745 monitorMAX6736XK_ _D_-T-40°C to +85°C5 SC70-5the primary Vpower-fail ly and have an independentMAX6737XK_ _D_-T*-40°C to +85°C5 SC70-5The MAX6736–MAX6745 monitor I/O supply voltages*Future product—contact factory for availability.(VCC1) from 1.8V to 5.0V and core supply voltages(VNote:The first “_ _” or “_” are placeholders for the thresholdthreshold voltage options (Table 1). An externalCC2) from 0.9V to 3.3V with factory-trimmed resetvoltage levels of the devices. Desired threshold levels are setadjustable RSTIN input option allows monitoring volt-by the part number suffix found in Tables 1 and 2. The “_” afterages down to D is a placeholder for the reset timeout period suffix foundin Table 3. For example, the MAX6736XKLTD3-T is a dual-volt-A variety of push-pull or open-drain reset outputs alongage supervisor Vwith manual reset input and power-fail input/output fea-minimum reset timeout period. All devices are available inTH1 = 4.625V, VTH2 = 3.075V, and a 150mstures are available (see the Selector Guide). Thetape-and-reel only. There is a 2500-piece minimum orderMAX6736–MAX6745 are offered in a space-saving 5-pinincrement for standard versions (see Table 1). Sample stock isSC70 package and operate over the -40°C to +85°Ctypically held on standard versions only. Nonstandard versionstemperature e a minimum order increment of 10,000 pieces. Contactfactory for availability.

ApplicationsOrdering Information continued at end of data le/Battery-ControllersSelector Guide continued at end of data d EquipmentPDAsPin Configurations appear at end of data oltage SystemsGPS EquipmentTypical Application Circuits appear at end of data ok ComputersPOS EquipmentFunctional Diagram appears at end of data or GuidePARTVOLTAGEOPEN-DRAINPUSH-PULLMANUALPOWER-FAILPOKRSTINMONITORSRESETRESETRESETINPUT/OUTPUTOUTPUTINPUTMAX67362 fixedX—X———MAX67372 fixed—XX———MAX67381 fixed, 1 adjX—X——X*Manual reset detect on

RESEToutput.________________________________________________________________Maxim Integrated Products1For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at

1-888-629-4642, or visit Maxim’s website at 6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745ABSOLUTE MAXIMUM RATINGSVCC1,

VCC2, POK1 -0.3V to +6VOpen-Drain RESET, -0.3V to +6VPush-Pull -0.3V to (VCC1 + 0.3V)MR, RSTIN, PFI -0.3V to (VCC1 + 0.3V)Input/Output Current, 20mAContinuous Power Dissipation (TA= +70°C)5-Pin SC70 (derate 3.1mW/°C above +70°C)..............247mWOperating -40°C to +85°+150°CStorage -65°C to +150°CLead Temperature (soldering, 10s).................................+300°CStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETEROperating Voltage RangeSYMBOLVCC1,VCC2CONDITIONSTA

= -40°C to 0°CTA = 0°C to +85°CVCC1 = 3.3V, VCC1 > VCC2, no load, resetnot assertedVCC1 = 1.8V, VCC1 < VCC2, no load, resetnot assertedVCC2 = 1.8V, VCC2

< VCC1, no load, resetnot assertedVCC2 = 3.3V, VCC2 > VCC1, no load, resetnot assertedMAX67_ _LMAX67_ _MMAX67_ _TMAX67_ _SReset Threshold for VCC1VTH1MAX67_ _RMAX67_ _ZMAX67_ _YMAX67_ _WMAX67_ _VTA = 0°C to +85°CTA = -40°C to +85°CTA

= 0°C to +85°CTA = -40°C to +85°CTA = 0°C to +85°CTA = -40°C to +85°CTA

= 0°C to +85°CTA

= -40°C to +85°CTA

= 0°C to +85°CTA = -40°C to +85°CTA

= 0°C to +85°CTA

= -40°C to +85°CTA

= 0°C to +85°CTA

= -40°C to +85°CTA

= 0°C to +85°CTA = -40°C to +85°CTA = 0°C to +85°CTA = -40°C to +85°C4.5004.4254.2504.1753.0002.9502.8502.8002.5502.5052.2502.2132.1252.0881.6201.5931.5301.5031.5751.6652.1882.3132.6252.9253.0754.375MIN1.21.0551104.625TYPMAX5.55.510µA102µA204.7504.8254.5004.5753.1503.2003.0003.0502.7002.7452.3752.4132.2502.2881.7101.7371.6201.647VUNITSVELECTRICAL CHARACTERISTICSVCC1 Supply CurrentICC1VCC2 Supply CurrentICC22_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsELECTRICAL CHARACTERISTICS (continued)(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSMAX67_ _TTA = 0°C to +85°C3.0003.0753.150TA

= -40°C to +85°C2.9053.050MAX67_ _STA

= 0°C to +85°C2.8502.9253.000TA = -40°C to +85°C2.8003.050MAX67_ _RTA = 0°C to +85°C2.5502.6252.700TA = -40°C to +85°C2.5052.745MAX67_ _ZTA = 0°C to +85°C2.2502.3132.375TA

= -40°C to +85°C2.2132.413MAX67_ _YTA

= 0°C to +85°C2.1252.1882.250TA

= -40°C to +85°C2.0882.288MAX67_ _WTA = 0°C to +85°C1.6201.6651.710TA

= -40°C to +85°C1.5931.737Reset Threshold for VT1.5301.5751.620CC2VTH2MAX67_ _VA = 0°C to +85°CTA = -40°C to +85°C1.5031.647VMAX67_ _ITA = 0°C to +85°C1.3501.3881.425TA = -40°C to +85°C1.3281.448MAX67_ _HTA = 0°C to +85°C1.2751.3131.350TA = -40°C to +85°C1.2531.373MAX67_ _GTA = 0°C to +85°C1.0801.1101.140TA

= -40°C to +85°C1.0621.158MAX67_ _FTA = 0°C to +85°C1.0201.0501.080TA

= -40°C to +85°C1.0021.098MAX67_ _ETA = 0°C to +85°C0.8100.8330.855TA = -40°C to +85°C0.7970.869MAX67_ _DTA = 0°C to + 85°C0.7650.7880.810TA = -40°C to +85°C0.7520.824RSTIN Threshold (MAX6738/TA = 0°C to +85°C0.4760.4880.500MAX6739/MAX6740/MAX6743)VTH-RSTINTA

= -40°C to +85°C0.4680.507VRSTIN Input CurrentVRSTIN ≥ 0.1V (Note 2)-10+10nAReset Threshold HysteresisVTH1, VTH2, RSTIN, PFI0.5%VCC1 ≥ 1.0V, ISINK

= 50µA, TA = 0°C to+85°C0.3RESET, POK1 Output LowVOLVCC1 ≥ 1.2V, ISINK

= 100µA0.3VVCC1 ≥ 2.13V, ISINK = 1.2mA0.3VCC1 ≥ 4.25V, ISINK

= 3.2mA,0.4VCC1 ≥ 2.38V, ISOURCE

= 500µA, output0.8 ×RESET Output High (Push-Pull)VdeassertedVCCOHVCC1 ≥ 4.75V, I0.8 ×VSOURCE

= 800µA, outputdeassertedVCC_______________________________________________________________________________________3MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745ELECTRICAL CHARACTERISTICS (continued)(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETERRESET Output Open-DrainLeakage Current(MAX6736/MAX6738)POK1 Output Open-DrainLeakageVCC Reset DelayVCC Reset Timeout Period(Note 3)MR to VCC1 Internal PullupImpedanceMR Timeout PeriodMR Minimum Input Pulse WidthMR Glitch RejectionVILMR Input VoltageVIHMR to RESET DelayVCC1 POWER-OK OUTPUT (MAX6741/MAX6744 only)POK1 Timeout PeriodRESET to VCC1 Internal PullupImpedanceManual Reset Detect DebouncePeriodManual Reset TimeoutPeriod (Note 3)Manual Reset Minimum InputPulse WidthManual Reset Release DetectThresholdManual Reset Glitch RejectionManual Reset to RESET DelaytDEBtMRPtMPW(Note 4)MAX67_ _ _ _ XK_ _D3MAX67_ _ _ _ XK_ _ D7(Note 4)(Note 4)(Note 4)tPOKP37.556.2575.0msPUSHBUTTON RESET (MAX6740/MAX6741/MAX6742 only)2537.5150120010.5 ×VCC.25225180010075.03002400kΩmsmsµsVnsns0.8 ×VCC1300tMRPtMPWBoth D3 and D7 timing optionstRDtRPSYMBOLILKGCONDITIONSOutput not asserted low (Note 2)MINTYPMAX500UNITSnAOutput not asserted low (Note 2)VCC1, VCC2, or RSTIN falling at 10mV/µsfrom VTH

+ 100mV to VTH

- 100mVMAX67_ _ _ _ XK_ _D3MAX67_ _ _ _ XK_ _ D71500500nAµs3002400msMANUAL RESET (MAX6736–MAX6739 only)0.7515011000.3 ×VCC11.52253.00300kΩmsµsnsVns4_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsELECTRICAL CHARACTERISTICS (continued)(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSPOWER-FAIL COMPARATOR (MAX6742/MAX6745 only)Power Fail In Threshold (Note 5)VTTH-PFIA

= 0°C to +85°C0.4760.4880.500TVA

= -40°C to +85°C0.4680.507Power Fail In CurrentIPFIVPFI ≥ 0.1V (Note 2)-10+10nAVCC1 ≥ 1.53V, ISINK = 500µA0.3PFO Output LowVOLVCC1 ≥ 2.03V, ISINK = 1.2mA0.3VVCC1 ≥ 4.25V, ISINK

= 3.2mA0.4PFI falling at 10mV/µs from VTH-PFI +PFI to PFO Propagation DelaytP100mV to VTH-PFI

- 100mV or rising at10mV/µs from VTH-PFI - 100mV to VTH-PFI

+35µs100mV (Note 5)PFO Startup DelayTo output valid (Note 5)5msNote 1:All devices are 100% tested at TNote 2:Guaranteed by design.A= +25°C. All temperature limits are guaranteed by 3:t2 (max) (MAX6741/MAX6744).Note 4:Refers to the manual reset function obtained by forcing the RESET output out period begins after POK1 timeout period (tPOKP) and VCC2 ≥VTHNote 5:VCC1 ≥l Operating Characteristics(TA

= +25°C, unless otherwise noted.)SUPPLY CURRENT vs. TEMPERATURESUPPLY CURRENT vs. TEMPERATURESUPPLY CURRENT vs. TEMPERATURE101023Vc0octo9CC1 = 3.3V, VCC2 = 2.5V10

t59VCC1 = 2.5V, VCC2 = 1.8V10

45-46-9V0CC1 = 1.8V, VCC2 = 1.2Vcot

54-3667336778X86AXMAM86XA)MA))µ7AA(µµ

TOTAL(7(7T

N6TTENNRE6E6RIRTOTALRU5CC1RRCUUC5C5TOTAL

Y

L4YICC1YPLLPP4P4UPPS3UUS3S3ICC12ICC2221I1CC21ICC2000-40-2-40-2-40-2TEMPERATURE (°C)TEMPERATURE (°C)TEMPERATURE (°C)_______________________________________________________________________________________5MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory Circuits45Typical Operating Characteristics (continued)(TA

= +25°C, unless otherwise noted.)76XAM–6376XAM6NORMALIZED VCC/POK1/MR

MAXIMUM VCC1/VCC2 TRANSIENT DURATIONTIMEOUT PERIOD vs. TEMPERATUREvs. RESET THRESHOLD OVERDRIVE)s1.0194µ10,000500c(co

ottN

554O4--T6I633E7T7S1.0146A6XXEARARMU

1000VCC1MRD

MDT/N1O1.009ERESET OCCURS ABOVEKIIORSETHESE LINESPPN/

ACT1.004RCUT100V

2

ODECEM0.999CZIV/ITL1A0.994CMCRV

10VCC2OMN0.989UMIXA0.984M0-40-21001000TEMPERATURE (°C)RESET THRESHOLD OVERDRIVE (mV)NORMALIZED VCC RESET THRESHOLDVCC TO RESET OUTPUT DELAYvs. TEMPERATUREvs. TEMPERATURE1.0086700cocot

5D4-L648.5100mV OVERDRIVEt

54)-63Os3776Hµ6XA(XS

EMYAMR1.003AHLET43.5

DT

ETSUEPR0.998T

CUCO

VT38.5

DEESEZIRL

AOM0.993T

RCC33.5ONV

NORMALIZED TO +25°C0.98828.5-40-2-40-2TEMPERATURE (°C)TEMPERATURE (°C)RESET INPUT TO RESET OUTPUT DELAYPOWER-FAIL INPUT TO POWER-FAIL

vs. TEMPERATUREOUTPUT DELAY vs. TEMPERATURE3589100mV OVERDRIVE0cot49100mV OVERDRIVE0cot

55)44s--66µ3377(66

YXXAAM)Ls44AMEDµ30(RISING EDGE

TYUAPLTED39UO

O

TFEPS

EORT25

34

IOFTP

NITSR29FALLING EDGE

2024-40-2-40-2TEMPERATURE (°C)TEMPERATURE (°C)_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsTypical Operating Characteristics (continued)(TA

= +25°C, unless otherwise noted.)POWER-FAIL INPUT TO

MR TO RESET OUTPUT DELAYPOWER-FAIL OUTPUT DELAYMAX6736-45 toc10MAX6736-45 toc11VPFIMR2V/div200mV/divVPFORESET2V/div2V/div100ns/div10µs/divOUTPUT LOW VOLTAGEVCC TO RESET OUTPUT DELAYvs. SINK CURRENTMAX6736-45 toc1250031VcCC = 3.3Vot

54-6376V)CCV400XA200mV/divmM(

EAC-COUPLEDGATL300OV

WOL

T200UPVTRESETU2V/divO10004µs/divSINK CURRENT (mA)OUTPUT HIGH VOLTAGEvs. SOURCE CURRENT441VcCC = 3.3Vot

54-6376X)VAM(

E3GATLOV

HG2IH

TUPTUO1000.250.500.751.001.251.501.752.00SOURCING CURRENT (mA)_______________________________________________________________________________________7MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745Pin DescriptionPINMAX6736MAX6738MAX6740MAX6741MAX6742MAX6737MAX6739MAX6743MAX6744MAX6745NAMEFUNCTIONReset Output, Push-Pull or Open Drain Active Low. RESETchanges from high to low when any monitored power-supplyinput (VCC1, VCC2, RSTIN) drops below its selected resetthreshold. It remains low until all monitored power-supplyinputs exceed their selected reset thresholds for the VCCreset timeout period. RESET is forced low if MR is low for atleast the MR minimum input pulse width. It remains low forthe MR reset timeout period after MR goes high. The push-pull output is referenced to VCC1. The MAX6736/MAX6738open-drain outputs require an external pullup resistor. TheMAX6740/MAX6741/MAX6742 open-drain outputs have aninternal 50kΩ pullup resistor to VCC1 and provide a manualreset Manual Reset, Active Low. Pull low for at least MR minimuminput pulse width to force RESET low. Reset remains activeas long as MR is low and for the MR reset timeout periodafter MR goes high. There is an internal 1.5kΩ pullup resistorto e Input 1. Power supply and input for the secondaryµP voltage reset able Reset Threshold Input. RESET is asserted whenRSTIN is below the internal 0.488V reference level. Set theadjustable reset threshold with an external resistor-dividernetwork. Connect RSTIN to VCC1 if e Input 2. Power supply and input for the primary µPvoltage reset -Fail Comparator Input. PFO is asserted when PFI isbelow 0.488V. PFO is deasserted without any reset timeoutperiod when PFI goes above 0.488V. Connect PFI to anexternal resistor network to set the desired -Fail Comparator Output, Open Drain Active Low. PFOis asserted when PFI is below 1 Power-OK Output, Open Drain Active High. POK1remains low as long as VCC1 is below VTH1.

POK1 outputgoes high after VCC1 exceeds VTH1 for the POK1 timeoutperiod. POK1 logic is independent of the MR or VCC2 output can be used to control VCC1-to-VCC2 supplysequencing.11111RESET22222GND33———MR4—44—VCC2—43——RSTIN55555VCC1————4PFI————3PFO———3—POK18_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsTable 1. Reset Voltage Threshold Suffix Guide for MAX6736/MAX6737/MAX6740/MAX6741/MAX6743/MAX6744PART 1 NOMINALVCC2 NOMINALPART 1 NOMINALVCC2 NOMINALSUFFIXVOLTAGEVOLTAGESUFFIXVOLTAGEVOLTAGE( _ _ )THRESHOLD (V)THRESHOLD (V)( _ _ )THRESHOLD (V)THRESHOLD (V)LT4.6253.075RD2.6250.788MS4.3752.925ZW2.3131.665MR4.3752.625ZI2.3131.388TZ3.0752.313ZG2.3131.110TW3.0751.665ZE2.3130.833TI3.0751.388YV2.1881.575TG3.0751.110YH2.1881.313TE3.0750.833YF2.1881.050SY2.9252.188YD2.1880.788SV2.9251.575WT1.6653.075SH2.9251.313WI1.6651.388SF2.9251.050WG1.6651.110SD2.9250.788WE1.6650.833RY2.6252.188VR1.5752.625RV2.6251.575VH1.5751.313RH2.6251.313VF1.5751.050RF2.6251.050VD1.5750.788Note: Standard versions, shown in bold, are available in the D3 timeout option only. Samples are typically held on standard versionsonly. There is a 10,000-piece order increment on nonstandard versions. Other threshold voltage combinations may be available;contact factory for 2. Reset Voltage Threshold SuffixGuide for MAX6738/MAX6739/MAX6742/Table 3. VCCTimeout Period SuffixMAX6745GuidePART 1 NOMINALTIMEOUT ACTIVE TIMEOUT PERIODSUFFIXVOLTAGEPERIOD( _ )THRESHOLD (V)SUFFIXMIN (ms)MAX (ms)L4.625D3150300M4.375D712002400T3.075S2.925R2.625Z2.313Y2.188W1.665V1.575Note:Standard versions, shown in bold, are available in theD3 timeout option only. Samples are typically held on standardversions only. There is a 10,000-piece order increment on non-standard versions. Other threshold voltages may be avail-able; contact factory for availability._______________________________________________________________________________________9MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745VCC1VTH1GNDPOK1tPOKPGNDVCC2VTH2GNDMRSWITCHBOUNCESWITCHBOUNCEGNDRESETtRPGNDtMRPFigure 1. Timing DiagramDetailed DescriptionSupply VoltagesThe MAX6736–MAX6745 µP supervisory circuits main-tain system integrity by alerting the µP to fault condi-tions. These devices are optimized for systems thatmonitor two or three supply voltages. The reset outputstate is guaranteed to remain valid while either VCC1 orVCC2 is above OutputThe MAX6736–MAX6745 provide an active-low reset out-put (RESET). RESETis asserted when the voltage ateither VCC1 or VCC2 falls below the voltage thresholdlevel, RSTIN drops below the threshold, or MRis pulledlow. Once reset is asserted, it stays low for the reset time-out period. If VCC1, VCC2, or RSTIN goes below the resetthreshold before the reset timeout period is completed,the internal timer restarts. The MAX6736/MAX6738/MAX6740/MAX6741/MAX6742 have open-drain reset out-puts, while the MAX6737/MAX6739/MAX6743/MAX6744/MAX6745 have push-pull reset outputs (Figure 1).The MAX6740/MAX6741/MAX6742 include a RESEToutput with a manual reset detect function. The open-drain RESEToutput has an internal 50kΩpullup toVCC1. The RESEToutput is low while the output ispulled to GND and remains low for at least the manualreset timeout period after the external GND pulldown isThreshold LevelsThe MAX6736/MAX6737/MAX6740/MAX6741/MAX6743/MAX6744 input voltage threshold combinations are indi-cated by a two-letter code in Table 1. The MAX6738/MAX6739/MAX6742/MAX6745 input voltage thresholdsare indicated by a one-letter code in Table 2. Contact thefactory for the availability of other voltage thresholds.10______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsSWITCHSWITCHSWITCHSWITCHBOUNCEBOUNCEBOUNCEBOUNCEOPENPUSHBUTTONSWITCHCLOSEDVCC1tDEBtMRPtDEBtMRPRESETGNDFigure 2. MAX6740/MAX6741/MAX6742 Manual Reset Timing Diagram

released. The manual reset detect function is internallycally 488mV. Connect a resistor-divider network to thedebounced for the tcircuit as shown in Figure 3 to establish an externallycan be connected directly to a momentary pushbuttonDEBtimeout period, so the outputcontrolled threshold voltage, Vswitch, if desired (Figure 2).EXT__TH= 0.488V((R1 + R2) / R2)Manual Reset InputMany microprocessor-based products require manualLow leakage current at RSTIN allows the use of large-reset capability, allowing the operator, a test techni-valued resistors, resulting in reduced power consump-cian, or external logic circuitry to initiate a reset whiletion of the monitored supplies remain above their reset thresh-Power-Fail Comparatorolds. The MAX6736–MAX6739 have a dedicatedPFI is the noninverting input to an auxiliary comparator. Aactive-low MRinput. The RESETis asserted low while488mV internal reference (VMRis held low and remains asserted for the manualinverting input of the comparator. If PFI is less thanTH-PFI) is connected to thereset timeout period after MRreturns high. The MR488mV, PFOis asserted low. PFOdeasserts without ainput has an internal 1.5kΩpullup resistor to VCC1andtimeout period when PFI rises above the externally setcan be left unconnected if not used. MRcan be driventhreshold. Common uses for the power-fail comparatorwith CMOS logic levels, open-drain/open-collector out-include monitoring for low battery conditions or a failingputs, or a momentary pushbutton switch to GND to cre-DC-DC converter input voltage (see the Typicalate a manual reset ation Circuits). The asserted PFOoutput can placeAdjustable Input Voltagea system in a low-power suspend mode or support anThe MAX6738/MAX6739 and MAX6740/MAX6743 pro-orderly system shutdown before monitored VCCvoltagesvide an additional input to monitor a second or thirddrop below the reset thresholds. Connect PFI to an exter-system voltage. The threshold voltage at RSTIN is typi-nal resistor-divider network as shown in Figure 4 to setthe desired trip threshold. Connect PFI to VCC1 if ations InformationInterfacing to the µP withVEXT_THMAX6738Bidirectional Reset PinsMost microprocessors with bidirectional reset pins canR1MAX6739MAX6740interface directly to open-drain RESEToutput s simultaneously requiring a push-pull RESETRSTINMAX6743output and a bidirectional reset interface can be inR2logic contention. To prevent contention, connect a4.7kΩresistor between RESETand the µP’s reset I/Oport as shown in Figure ure 3. Monitoring an Additional Voltage______________________________________________________________________________________11MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745A) VIN IS POSITIVEVEXT_THR1PFIR2MAX6742MAX6745PFOVEXT_TH = VTH-PFI(R1 + R2R2)GNDshown in Figure 6. Select the values of R1, R2, and R3such that PFI sees VTH-PFI(488mV) when VEXTfalls toits power-fail trip point (VFAIL) and when VEXTrises toits power-good trip point (VGOOD). The hysteresis win-dow extends between the specified VFAILand VGOODthresholds. R3 adds the additional hysteresis by sink-ing current from the R1/R2 divider network when thePFOoutput is logic low and sourcing current into thenetwork when PFOis logic high. R3 is typically an orderof magnitude greater than R1 or current through R2 should be at least 1µA to ensurethat the 10nA (max) PFI input current does not significant-ly shift the trip points. Therefore, for most applications:R2 < VTH-PFI/ 1mA < 0.488V / 1mA < 488kΩPFOis an open-drain output requiring an externalpullup resistor, R4. Select R4 to be less than 1% of = DESIRED VEXTGOOD VOLTAGE THRESHOLDVFAIL= DESIRED VEXTFAIL VOLTAGE THRESHOLDVPU= VPULLUP(FOR OPEN-DRAIN PFO)R2 = 488kΩ(FOR >1µA R2 CURRENT)B) VIN IS NEGATIVEVCCR1PFIR2MAX6742MAX6745PFOVEXT_TH = R2(VTH-PFI)VPFI

= 488mV

(( )V1+1-CCR1R1R2)VEXT_THGNDFigure 4. Using Power-Fail Input to Monitor an AdditionalPower SupplyR1=R2

(VGOOD-VTH−PFI

−

)(VTH-PFI(VGOOD-VFAIL)VPUVTH-PFIAdding Hysteresis to thePower-Fail ComparatorThe power-fail comparator has a typical input hystere-sis of 2.5mV. This is sufficient for most applications inwhich a power-supply line is being monitored throughan external voltage-divider. If additional noise margin isdesired, connect a resistor between PFOand PFI, asR3 = (R1 x VPU) / (VGOOD- VFAIL)R4 ≤0.01 x R3Power Sequencing ApplicationsMany dual-voltage processors/ASICs require specificpower-up/power-down sequences for the I/O and coresupplies.

VCC1VCC2RESET TO OTHER SYSTEM COMPONENTSR3VPULLUPVGOODVFAILVINVCC2VCC1MAX6737MAX6739MAX6743MAX6744RESETMAX6745VEXTMAX6742MAX6745R1PFIR2PFOR4PFO4.7kΩRESETµPGNDGNDGNDVGOOD = DESIRED VEXT GOOD VOLTAGE THRESHOLDVFAIL = DESIRED VEXT FAIL VOLTAGE THRESHOLDVOH = VCC1 (FOR PUSH-PULL PFO)R2 = 200kΩ (FOR > 2.5µA R2 CURRENT)R1 = R2 ((VGOOD - VTH-PFI) - (VTH-PFI)(VGOOD - VFAIL) / VPU) / VTH-PFIR3 = (R1 x VOH) / (VGOOD - VFAIL)Figure 5. Interfacing to µPs with Bidirectional Reset I/O12Figure 6. Adding Hysteresis to Power Fail for Push-Pull

PFO______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsThe MAX6741/MAX6744 offer a VCC1 POK (POK1) idealTransient Immunityfor VThe MAX6736–MAX6745 supervisors are relativelylong as VCC1-to-V1 is below its VCC2 sequencing. POK1 remains low asCCTH1 threshold. When VCC1immune to short-duration falling Vexceeds Ves). It is usually undesirable to reset the µP when VCCtransients (glitch-open-drain POK1 output is deasserted. The POK1 outputTH1 for the POK1 timeout period (tPOKP), theexperiences only small glitches. The Typical OperatingCCcan then enable the VCharacteristics show Maximum VPOK1 pullup resistor).

CC2 power supply (use an externalRESETis deasserted when bothCC1/VCC2TransientDuration vs. Reset Threshold Overdrive, for which resetVCC1 and VCC2 remain above their selected thresholdspulses are not generated. The graph shows the maxi-for the reset timeout period (tmum pulse width that a falling Vbe used for I/O before core or core before I/O sequenc-RP). The POK1 output canCCtransient might typi-cally have without causing a reset pulse to be , depending on the selected VAs the amplitude of the transient increases, the maxi-See the Typical Application Circuit

CC1/Vand Figure 2 allowable pulse width decreases. A 0.1µF bypassMonitoring a Negative Voltagecapacitor mounted close to the VCCpin provides addi-The power-fail comparator can be used to monitor ational transient ve supply voltage using the circuit shown inFigure 4. When the negative supply is valid, PFOis the negative supply voltage drops, PFOgoesChip Informationhigh. The circuit’s accuracy is affected by the PFITRANSISTOR COUNT: 249threshold tolerance, VCC, R1, and S: BiCMOSFunctional DiagramVCC1MAX6736–MAX6745PFODELAYPOK1VCC1VCC2RSTIN/PFIRESETTIMEOUTRESETPERIODOUTPUTRESETVCC2VCC1MRPULLUP0.488VVCC11.23VMR______________________________________________________________________________________13MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745Selector Guide (continued)PARTMAX6739MAX6740MAX6741MAX6742MAX6743MAX6744MAX6745VOLTAGEMONITORS1 fixed, 1 adj2 fixed, 1 adj2 fixed1 fixed2 fixed, 1adj2 fixed1 fixedOPEN-DRAINRESET—X*X*X*———PUSH-PULLRESETX———XXXMANUALRESETXX*X*X*———POWER-FAILINPUT/OUTPUT———X——XPOKOUTPUT——X——X—RSTININPUTXX——X——*Manual reset detect on

l Application CircuitsDC/DCCONVERTERUNREGULATEDDCINOUTVBATTINOUTDC/DCCONVERTERVCC1VCC2VCC1COREI/OSUPPLYSUPPLYµPINOUTDC/DCCONVERTERSHDNPFOMAX6742VCCµPPFIGNDRESETMAX6741RESETGNDPOK1GNDRESETRESETGNDPUSHBUTTONSWITCHPUSHBUTTONSWITCH14______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsPin ConfigurationsTOP VIEWRESET15VCC1RESET15VCC1RESET15VCC1GND2MAX6736MAX6737GND2MAX6738MAX6739GND2MAX6740MAX6743MR34VCC2MR34RSTINRSTIN34VCC2SC70SC70SC70RESET15VCC1RESET15VCC1GND2MAX6741MAX6744GND2MAX6742MAX6745POK134VCC2PFO34PFISC70SC70Ordering Information (continued)PARTTEMP RANGEPIN-PACKAGEMAX6738XK_D_-T*-40°C to +85°C5 SC70-5MAX6739XK_D_-T-40°C to +85°C5 SC70-5MAX6740XK_ _D_-T-40°C to +85°C5 SC70-5MAX6741XK_ _D_-T-40°C to +85°C5 SC70-5MAX6742XK_D_-T-40°C to +85°C5 SC70-5MAX6743XK_ _D_-T*-40°C to +85°C5 SC70-5MAX6744XK_ _D_-T*-40°C to +85°C5 SC70-5MAX6745XK_D_-T-40°C to +85°C5 SC70-5*Future product—contact factory for availability.______________________________________________________________________________________15MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745Package 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.)SC70,

im cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time.16____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2002 Maxim Integrated Products Printed USAis a registered trademark of Maxim Integrated Products.

2024年2月25日发(作者：刀醉易)

元器件交易网19-2531; Rev 0; 10/02Low-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsGeneral DescriptionFeaturesThe MAX6736–MAX6745 are low-power dual-/triple-voltage microprocessor (µP) supervisors. TheseoDual-/Triple-Supply Reset Voltage Monitorsdevices assert a reset if any monitored supply fallsoPrecision Factory-Set Reset Thresholds forbelow its factory-trimmed or adjustable threshold andMonitoring from 0.9V to 5.0Vmaintain reset for a minimum timeout period after alloAdjustable Reset Input Down to 0.488Vsupplies rise above their thresholds. The integratedo150ms and 1200ms (min) Reset Timeout Perioddual/triple supervisory circuits significantly reduce sizeOptionsand power compared to separate ICs or discrete com-ponents. The low supply current of 6µA makes theseoVCC1 Power-OK Output for Power-Supplydevices ideal for portable cing Applications (MAX6741/MAX6744)The MAX6736/MAX6737 are dual fixed-voltage µPoPower-Fail Input/Power-Fail Outputsupervisors with a manual reset input. The MAX6738/(MAX6742/MAX6745)MAX6739 have one fixed and one adjustable reseto6µA Supply Currentthreshold and a manual reset input. The MAX6740/oTiny SC70 PackageMAX6743 are triple-voltage µP supervisors with twofixed and one user-adjustable reset threshold ng InformationThe MAX6741/MAX6744 are dual-voltage µP supervi-sors with a power-OK (POK) output ideal for power-PARTTEMP RANGEPIN-PACKAGEsupply sequencing. The MAX6742/MAX6745 monitorMAX6736XK_ _D_-T-40°C to +85°C5 SC70-5the primary Vpower-fail ly and have an independentMAX6737XK_ _D_-T*-40°C to +85°C5 SC70-5The MAX6736–MAX6745 monitor I/O supply voltages*Future product—contact factory for availability.(VCC1) from 1.8V to 5.0V and core supply voltages(VNote:The first “_ _” or “_” are placeholders for the thresholdthreshold voltage options (Table 1). An externalCC2) from 0.9V to 3.3V with factory-trimmed resetvoltage levels of the devices. Desired threshold levels are setadjustable RSTIN input option allows monitoring volt-by the part number suffix found in Tables 1 and 2. The “_” afterages down to D is a placeholder for the reset timeout period suffix foundin Table 3. For example, the MAX6736XKLTD3-T is a dual-volt-A variety of push-pull or open-drain reset outputs alongage supervisor Vwith manual reset input and power-fail input/output fea-minimum reset timeout period. All devices are available inTH1 = 4.625V, VTH2 = 3.075V, and a 150mstures are available (see the Selector Guide). Thetape-and-reel only. There is a 2500-piece minimum orderMAX6736–MAX6745 are offered in a space-saving 5-pinincrement for standard versions (see Table 1). Sample stock isSC70 package and operate over the -40°C to +85°Ctypically held on standard versions only. Nonstandard versionstemperature e a minimum order increment of 10,000 pieces. Contactfactory for availability.

ApplicationsOrdering Information continued at end of data le/Battery-ControllersSelector Guide continued at end of data d EquipmentPDAsPin Configurations appear at end of data oltage SystemsGPS EquipmentTypical Application Circuits appear at end of data ok ComputersPOS EquipmentFunctional Diagram appears at end of data or GuidePARTVOLTAGEOPEN-DRAINPUSH-PULLMANUALPOWER-FAILPOKRSTINMONITORSRESETRESETRESETINPUT/OUTPUTOUTPUTINPUTMAX67362 fixedX—X———MAX67372 fixed—XX———MAX67381 fixed, 1 adjX—X——X*Manual reset detect on

RESEToutput.________________________________________________________________Maxim Integrated Products1For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at

1-888-629-4642, or visit Maxim’s website at 6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745ABSOLUTE MAXIMUM RATINGSVCC1,

VCC2, POK1 -0.3V to +6VOpen-Drain RESET, -0.3V to +6VPush-Pull -0.3V to (VCC1 + 0.3V)MR, RSTIN, PFI -0.3V to (VCC1 + 0.3V)Input/Output Current, 20mAContinuous Power Dissipation (TA= +70°C)5-Pin SC70 (derate 3.1mW/°C above +70°C)..............247mWOperating -40°C to +85°+150°CStorage -65°C to +150°CLead Temperature (soldering, 10s).................................+300°CStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETEROperating Voltage RangeSYMBOLVCC1,VCC2CONDITIONSTA

= -40°C to 0°CTA = 0°C to +85°CVCC1 = 3.3V, VCC1 > VCC2, no load, resetnot assertedVCC1 = 1.8V, VCC1 < VCC2, no load, resetnot assertedVCC2 = 1.8V, VCC2

< VCC1, no load, resetnot assertedVCC2 = 3.3V, VCC2 > VCC1, no load, resetnot assertedMAX67_ _LMAX67_ _MMAX67_ _TMAX67_ _SReset Threshold for VCC1VTH1MAX67_ _RMAX67_ _ZMAX67_ _YMAX67_ _WMAX67_ _VTA = 0°C to +85°CTA = -40°C to +85°CTA

= 0°C to +85°CTA = -40°C to +85°CTA = 0°C to +85°CTA = -40°C to +85°CTA

= 0°C to +85°CTA

= -40°C to +85°CTA

= 0°C to +85°CTA = -40°C to +85°CTA

= 0°C to +85°CTA

= -40°C to +85°CTA

= 0°C to +85°CTA

= -40°C to +85°CTA

= 0°C to +85°CTA = -40°C to +85°CTA = 0°C to +85°CTA = -40°C to +85°C4.5004.4254.2504.1753.0002.9502.8502.8002.5502.5052.2502.2132.1252.0881.6201.5931.5301.5031.5751.6652.1882.3132.6252.9253.0754.375MIN1.21.0551104.625TYPMAX5.55.510µA102µA204.7504.8254.5004.5753.1503.2003.0003.0502.7002.7452.3752.4132.2502.2881.7101.7371.6201.647VUNITSVELECTRICAL CHARACTERISTICSVCC1 Supply CurrentICC1VCC2 Supply CurrentICC22_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsELECTRICAL CHARACTERISTICS (continued)(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSMAX67_ _TTA = 0°C to +85°C3.0003.0753.150TA

= -40°C to +85°C2.9053.050MAX67_ _STA

= 0°C to +85°C2.8502.9253.000TA = -40°C to +85°C2.8003.050MAX67_ _RTA = 0°C to +85°C2.5502.6252.700TA = -40°C to +85°C2.5052.745MAX67_ _ZTA = 0°C to +85°C2.2502.3132.375TA

= -40°C to +85°C2.2132.413MAX67_ _YTA

= 0°C to +85°C2.1252.1882.250TA

= -40°C to +85°C2.0882.288MAX67_ _WTA = 0°C to +85°C1.6201.6651.710TA

= -40°C to +85°C1.5931.737Reset Threshold for VT1.5301.5751.620CC2VTH2MAX67_ _VA = 0°C to +85°CTA = -40°C to +85°C1.5031.647VMAX67_ _ITA = 0°C to +85°C1.3501.3881.425TA = -40°C to +85°C1.3281.448MAX67_ _HTA = 0°C to +85°C1.2751.3131.350TA = -40°C to +85°C1.2531.373MAX67_ _GTA = 0°C to +85°C1.0801.1101.140TA

= -40°C to +85°C1.0621.158MAX67_ _FTA = 0°C to +85°C1.0201.0501.080TA

= -40°C to +85°C1.0021.098MAX67_ _ETA = 0°C to +85°C0.8100.8330.855TA = -40°C to +85°C0.7970.869MAX67_ _DTA = 0°C to + 85°C0.7650.7880.810TA = -40°C to +85°C0.7520.824RSTIN Threshold (MAX6738/TA = 0°C to +85°C0.4760.4880.500MAX6739/MAX6740/MAX6743)VTH-RSTINTA

= -40°C to +85°C0.4680.507VRSTIN Input CurrentVRSTIN ≥ 0.1V (Note 2)-10+10nAReset Threshold HysteresisVTH1, VTH2, RSTIN, PFI0.5%VCC1 ≥ 1.0V, ISINK

= 50µA, TA = 0°C to+85°C0.3RESET, POK1 Output LowVOLVCC1 ≥ 1.2V, ISINK

= 100µA0.3VVCC1 ≥ 2.13V, ISINK = 1.2mA0.3VCC1 ≥ 4.25V, ISINK

= 3.2mA,0.4VCC1 ≥ 2.38V, ISOURCE

= 500µA, output0.8 ×RESET Output High (Push-Pull)VdeassertedVCCOHVCC1 ≥ 4.75V, I0.8 ×VSOURCE

= 800µA, outputdeassertedVCC_______________________________________________________________________________________3MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745ELECTRICAL CHARACTERISTICS (continued)(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETERRESET Output Open-DrainLeakage Current(MAX6736/MAX6738)POK1 Output Open-DrainLeakageVCC Reset DelayVCC Reset Timeout Period(Note 3)MR to VCC1 Internal PullupImpedanceMR Timeout PeriodMR Minimum Input Pulse WidthMR Glitch RejectionVILMR Input VoltageVIHMR to RESET DelayVCC1 POWER-OK OUTPUT (MAX6741/MAX6744 only)POK1 Timeout PeriodRESET to VCC1 Internal PullupImpedanceManual Reset Detect DebouncePeriodManual Reset TimeoutPeriod (Note 3)Manual Reset Minimum InputPulse WidthManual Reset Release DetectThresholdManual Reset Glitch RejectionManual Reset to RESET DelaytDEBtMRPtMPW(Note 4)MAX67_ _ _ _ XK_ _D3MAX67_ _ _ _ XK_ _ D7(Note 4)(Note 4)(Note 4)tPOKP37.556.2575.0msPUSHBUTTON RESET (MAX6740/MAX6741/MAX6742 only)2537.5150120010.5 ×VCC.25225180010075.03002400kΩmsmsµsVnsns0.8 ×VCC1300tMRPtMPWBoth D3 and D7 timing optionstRDtRPSYMBOLILKGCONDITIONSOutput not asserted low (Note 2)MINTYPMAX500UNITSnAOutput not asserted low (Note 2)VCC1, VCC2, or RSTIN falling at 10mV/µsfrom VTH

+ 100mV to VTH

- 100mVMAX67_ _ _ _ XK_ _D3MAX67_ _ _ _ XK_ _ D71500500nAµs3002400msMANUAL RESET (MAX6736–MAX6739 only)0.7515011000.3 ×VCC11.52253.00300kΩmsµsnsVns4_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsELECTRICAL CHARACTERISTICS (continued)(VCC= 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSPOWER-FAIL COMPARATOR (MAX6742/MAX6745 only)Power Fail In Threshold (Note 5)VTTH-PFIA

= 0°C to +85°C0.4760.4880.500TVA

= -40°C to +85°C0.4680.507Power Fail In CurrentIPFIVPFI ≥ 0.1V (Note 2)-10+10nAVCC1 ≥ 1.53V, ISINK = 500µA0.3PFO Output LowVOLVCC1 ≥ 2.03V, ISINK = 1.2mA0.3VVCC1 ≥ 4.25V, ISINK

= 3.2mA0.4PFI falling at 10mV/µs from VTH-PFI +PFI to PFO Propagation DelaytP100mV to VTH-PFI

- 100mV or rising at10mV/µs from VTH-PFI - 100mV to VTH-PFI

+35µs100mV (Note 5)PFO Startup DelayTo output valid (Note 5)5msNote 1:All devices are 100% tested at TNote 2:Guaranteed by design.A= +25°C. All temperature limits are guaranteed by 3:t2 (max) (MAX6741/MAX6744).Note 4:Refers to the manual reset function obtained by forcing the RESET output out period begins after POK1 timeout period (tPOKP) and VCC2 ≥VTHNote 5:VCC1 ≥l Operating Characteristics(TA

= +25°C, unless otherwise noted.)SUPPLY CURRENT vs. TEMPERATURESUPPLY CURRENT vs. TEMPERATURESUPPLY CURRENT vs. TEMPERATURE101023Vc0octo9CC1 = 3.3V, VCC2 = 2.5V10

t59VCC1 = 2.5V, VCC2 = 1.8V10

45-46-9V0CC1 = 1.8V, VCC2 = 1.2Vcot

54-3667336778X86AXMAM86XA)MA))µ7AA(µµ

TOTAL(7(7T

N6TTENNRE6E6RIRTOTALRU5CC1RRCUUC5C5TOTAL

Y

L4YICC1YPLLPP4P4UPPS3UUS3S3ICC12ICC2221I1CC21ICC2000-40-2-40-2-40-2TEMPERATURE (°C)TEMPERATURE (°C)TEMPERATURE (°C)_______________________________________________________________________________________5MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory Circuits45Typical Operating Characteristics (continued)(TA

= +25°C, unless otherwise noted.)76XAM–6376XAM6NORMALIZED VCC/POK1/MR

MAXIMUM VCC1/VCC2 TRANSIENT DURATIONTIMEOUT PERIOD vs. TEMPERATUREvs. RESET THRESHOLD OVERDRIVE)s1.0194µ10,000500c(co

ottN

554O4--T6I633E7T7S1.0146A6XXEARARMU

1000VCC1MRD

MDT/N1O1.009ERESET OCCURS ABOVEKIIORSETHESE LINESPPN/

ACT1.004RCUT100V

2

ODECEM0.999CZIV/ITL1A0.994CMCRV

10VCC2OMN0.989UMIXA0.984M0-40-21001000TEMPERATURE (°C)RESET THRESHOLD OVERDRIVE (mV)NORMALIZED VCC RESET THRESHOLDVCC TO RESET OUTPUT DELAYvs. TEMPERATUREvs. TEMPERATURE1.0086700cocot

5D4-L648.5100mV OVERDRIVEt

54)-63Os3776Hµ6XA(XS

EMYAMR1.003AHLET43.5

DT

ETSUEPR0.998T

CUCO

VT38.5

DEESEZIRL

AOM0.993T

RCC33.5ONV

NORMALIZED TO +25°C0.98828.5-40-2-40-2TEMPERATURE (°C)TEMPERATURE (°C)RESET INPUT TO RESET OUTPUT DELAYPOWER-FAIL INPUT TO POWER-FAIL

vs. TEMPERATUREOUTPUT DELAY vs. TEMPERATURE3589100mV OVERDRIVE0cot49100mV OVERDRIVE0cot

55)44s--66µ3377(66

YXXAAM)Ls44AMEDµ30(RISING EDGE

TYUAPLTED39UO

O

TFEPS

EORT25

34

IOFTP

NITSR29FALLING EDGE

2024-40-2-40-2TEMPERATURE (°C)TEMPERATURE (°C)_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsTypical Operating Characteristics (continued)(TA

= +25°C, unless otherwise noted.)POWER-FAIL INPUT TO

MR TO RESET OUTPUT DELAYPOWER-FAIL OUTPUT DELAYMAX6736-45 toc10MAX6736-45 toc11VPFIMR2V/div200mV/divVPFORESET2V/div2V/div100ns/div10µs/divOUTPUT LOW VOLTAGEVCC TO RESET OUTPUT DELAYvs. SINK CURRENTMAX6736-45 toc1250031VcCC = 3.3Vot

54-6376V)CCV400XA200mV/divmM(

EAC-COUPLEDGATL300OV

WOL

T200UPVTRESETU2V/divO10004µs/divSINK CURRENT (mA)OUTPUT HIGH VOLTAGEvs. SOURCE CURRENT441VcCC = 3.3Vot

54-6376X)VAM(

E3GATLOV

HG2IH

TUPTUO1000.250.500.751.001.251.501.752.00SOURCING CURRENT (mA)_______________________________________________________________________________________7MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745Pin DescriptionPINMAX6736MAX6738MAX6740MAX6741MAX6742MAX6737MAX6739MAX6743MAX6744MAX6745NAMEFUNCTIONReset Output, Push-Pull or Open Drain Active Low. RESETchanges from high to low when any monitored power-supplyinput (VCC1, VCC2, RSTIN) drops below its selected resetthreshold. It remains low until all monitored power-supplyinputs exceed their selected reset thresholds for the VCCreset timeout period. RESET is forced low if MR is low for atleast the MR minimum input pulse width. It remains low forthe MR reset timeout period after MR goes high. The push-pull output is referenced to VCC1. The MAX6736/MAX6738open-drain outputs require an external pullup resistor. TheMAX6740/MAX6741/MAX6742 open-drain outputs have aninternal 50kΩ pullup resistor to VCC1 and provide a manualreset Manual Reset, Active Low. Pull low for at least MR minimuminput pulse width to force RESET low. Reset remains activeas long as MR is low and for the MR reset timeout periodafter MR goes high. There is an internal 1.5kΩ pullup resistorto e Input 1. Power supply and input for the secondaryµP voltage reset able Reset Threshold Input. RESET is asserted whenRSTIN is below the internal 0.488V reference level. Set theadjustable reset threshold with an external resistor-dividernetwork. Connect RSTIN to VCC1 if e Input 2. Power supply and input for the primary µPvoltage reset -Fail Comparator Input. PFO is asserted when PFI isbelow 0.488V. PFO is deasserted without any reset timeoutperiod when PFI goes above 0.488V. Connect PFI to anexternal resistor network to set the desired -Fail Comparator Output, Open Drain Active Low. PFOis asserted when PFI is below 1 Power-OK Output, Open Drain Active High. POK1remains low as long as VCC1 is below VTH1.

POK1 outputgoes high after VCC1 exceeds VTH1 for the POK1 timeoutperiod. POK1 logic is independent of the MR or VCC2 output can be used to control VCC1-to-VCC2 supplysequencing.11111RESET22222GND33———MR4—44—VCC2—43——RSTIN55555VCC1————4PFI————3PFO———3—POK18_______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsTable 1. Reset Voltage Threshold Suffix Guide for MAX6736/MAX6737/MAX6740/MAX6741/MAX6743/MAX6744PART 1 NOMINALVCC2 NOMINALPART 1 NOMINALVCC2 NOMINALSUFFIXVOLTAGEVOLTAGESUFFIXVOLTAGEVOLTAGE( _ _ )THRESHOLD (V)THRESHOLD (V)( _ _ )THRESHOLD (V)THRESHOLD (V)LT4.6253.075RD2.6250.788MS4.3752.925ZW2.3131.665MR4.3752.625ZI2.3131.388TZ3.0752.313ZG2.3131.110TW3.0751.665ZE2.3130.833TI3.0751.388YV2.1881.575TG3.0751.110YH2.1881.313TE3.0750.833YF2.1881.050SY2.9252.188YD2.1880.788SV2.9251.575WT1.6653.075SH2.9251.313WI1.6651.388SF2.9251.050WG1.6651.110SD2.9250.788WE1.6650.833RY2.6252.188VR1.5752.625RV2.6251.575VH1.5751.313RH2.6251.313VF1.5751.050RF2.6251.050VD1.5750.788Note: Standard versions, shown in bold, are available in the D3 timeout option only. Samples are typically held on standard versionsonly. There is a 10,000-piece order increment on nonstandard versions. Other threshold voltage combinations may be available;contact factory for 2. Reset Voltage Threshold SuffixGuide for MAX6738/MAX6739/MAX6742/Table 3. VCCTimeout Period SuffixMAX6745GuidePART 1 NOMINALTIMEOUT ACTIVE TIMEOUT PERIODSUFFIXVOLTAGEPERIOD( _ )THRESHOLD (V)SUFFIXMIN (ms)MAX (ms)L4.625D3150300M4.375D712002400T3.075S2.925R2.625Z2.313Y2.188W1.665V1.575Note:Standard versions, shown in bold, are available in theD3 timeout option only. Samples are typically held on standardversions only. There is a 10,000-piece order increment on non-standard versions. Other threshold voltages may be avail-able; contact factory for availability._______________________________________________________________________________________9MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745VCC1VTH1GNDPOK1tPOKPGNDVCC2VTH2GNDMRSWITCHBOUNCESWITCHBOUNCEGNDRESETtRPGNDtMRPFigure 1. Timing DiagramDetailed DescriptionSupply VoltagesThe MAX6736–MAX6745 µP supervisory circuits main-tain system integrity by alerting the µP to fault condi-tions. These devices are optimized for systems thatmonitor two or three supply voltages. The reset outputstate is guaranteed to remain valid while either VCC1 orVCC2 is above OutputThe MAX6736–MAX6745 provide an active-low reset out-put (RESET). RESETis asserted when the voltage ateither VCC1 or VCC2 falls below the voltage thresholdlevel, RSTIN drops below the threshold, or MRis pulledlow. Once reset is asserted, it stays low for the reset time-out period. If VCC1, VCC2, or RSTIN goes below the resetthreshold before the reset timeout period is completed,the internal timer restarts. The MAX6736/MAX6738/MAX6740/MAX6741/MAX6742 have open-drain reset out-puts, while the MAX6737/MAX6739/MAX6743/MAX6744/MAX6745 have push-pull reset outputs (Figure 1).The MAX6740/MAX6741/MAX6742 include a RESEToutput with a manual reset detect function. The open-drain RESEToutput has an internal 50kΩpullup toVCC1. The RESEToutput is low while the output ispulled to GND and remains low for at least the manualreset timeout period after the external GND pulldown isThreshold LevelsThe MAX6736/MAX6737/MAX6740/MAX6741/MAX6743/MAX6744 input voltage threshold combinations are indi-cated by a two-letter code in Table 1. The MAX6738/MAX6739/MAX6742/MAX6745 input voltage thresholdsare indicated by a one-letter code in Table 2. Contact thefactory for the availability of other voltage thresholds.10______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsSWITCHSWITCHSWITCHSWITCHBOUNCEBOUNCEBOUNCEBOUNCEOPENPUSHBUTTONSWITCHCLOSEDVCC1tDEBtMRPtDEBtMRPRESETGNDFigure 2. MAX6740/MAX6741/MAX6742 Manual Reset Timing Diagram

released. The manual reset detect function is internallycally 488mV. Connect a resistor-divider network to thedebounced for the tcircuit as shown in Figure 3 to establish an externallycan be connected directly to a momentary pushbuttonDEBtimeout period, so the outputcontrolled threshold voltage, Vswitch, if desired (Figure 2).EXT__TH= 0.488V((R1 + R2) / R2)Manual Reset InputMany microprocessor-based products require manualLow leakage current at RSTIN allows the use of large-reset capability, allowing the operator, a test techni-valued resistors, resulting in reduced power consump-cian, or external logic circuitry to initiate a reset whiletion of the monitored supplies remain above their reset thresh-Power-Fail Comparatorolds. The MAX6736–MAX6739 have a dedicatedPFI is the noninverting input to an auxiliary comparator. Aactive-low MRinput. The RESETis asserted low while488mV internal reference (VMRis held low and remains asserted for the manualinverting input of the comparator. If PFI is less thanTH-PFI) is connected to thereset timeout period after MRreturns high. The MR488mV, PFOis asserted low. PFOdeasserts without ainput has an internal 1.5kΩpullup resistor to VCC1andtimeout period when PFI rises above the externally setcan be left unconnected if not used. MRcan be driventhreshold. Common uses for the power-fail comparatorwith CMOS logic levels, open-drain/open-collector out-include monitoring for low battery conditions or a failingputs, or a momentary pushbutton switch to GND to cre-DC-DC converter input voltage (see the Typicalate a manual reset ation Circuits). The asserted PFOoutput can placeAdjustable Input Voltagea system in a low-power suspend mode or support anThe MAX6738/MAX6739 and MAX6740/MAX6743 pro-orderly system shutdown before monitored VCCvoltagesvide an additional input to monitor a second or thirddrop below the reset thresholds. Connect PFI to an exter-system voltage. The threshold voltage at RSTIN is typi-nal resistor-divider network as shown in Figure 4 to setthe desired trip threshold. Connect PFI to VCC1 if ations InformationInterfacing to the µP withVEXT_THMAX6738Bidirectional Reset PinsMost microprocessors with bidirectional reset pins canR1MAX6739MAX6740interface directly to open-drain RESEToutput s simultaneously requiring a push-pull RESETRSTINMAX6743output and a bidirectional reset interface can be inR2logic contention. To prevent contention, connect a4.7kΩresistor between RESETand the µP’s reset I/Oport as shown in Figure ure 3. Monitoring an Additional Voltage______________________________________________________________________________________11MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745A) VIN IS POSITIVEVEXT_THR1PFIR2MAX6742MAX6745PFOVEXT_TH = VTH-PFI(R1 + R2R2)GNDshown in Figure 6. Select the values of R1, R2, and R3such that PFI sees VTH-PFI(488mV) when VEXTfalls toits power-fail trip point (VFAIL) and when VEXTrises toits power-good trip point (VGOOD). The hysteresis win-dow extends between the specified VFAILand VGOODthresholds. R3 adds the additional hysteresis by sink-ing current from the R1/R2 divider network when thePFOoutput is logic low and sourcing current into thenetwork when PFOis logic high. R3 is typically an orderof magnitude greater than R1 or current through R2 should be at least 1µA to ensurethat the 10nA (max) PFI input current does not significant-ly shift the trip points. Therefore, for most applications:R2 < VTH-PFI/ 1mA < 0.488V / 1mA < 488kΩPFOis an open-drain output requiring an externalpullup resistor, R4. Select R4 to be less than 1% of = DESIRED VEXTGOOD VOLTAGE THRESHOLDVFAIL= DESIRED VEXTFAIL VOLTAGE THRESHOLDVPU= VPULLUP(FOR OPEN-DRAIN PFO)R2 = 488kΩ(FOR >1µA R2 CURRENT)B) VIN IS NEGATIVEVCCR1PFIR2MAX6742MAX6745PFOVEXT_TH = R2(VTH-PFI)VPFI

= 488mV

(( )V1+1-CCR1R1R2)VEXT_THGNDFigure 4. Using Power-Fail Input to Monitor an AdditionalPower SupplyR1=R2

(VGOOD-VTH−PFI

−

)(VTH-PFI(VGOOD-VFAIL)VPUVTH-PFIAdding Hysteresis to thePower-Fail ComparatorThe power-fail comparator has a typical input hystere-sis of 2.5mV. This is sufficient for most applications inwhich a power-supply line is being monitored throughan external voltage-divider. If additional noise margin isdesired, connect a resistor between PFOand PFI, asR3 = (R1 x VPU) / (VGOOD- VFAIL)R4 ≤0.01 x R3Power Sequencing ApplicationsMany dual-voltage processors/ASICs require specificpower-up/power-down sequences for the I/O and coresupplies.

VCC1VCC2RESET TO OTHER SYSTEM COMPONENTSR3VPULLUPVGOODVFAILVINVCC2VCC1MAX6737MAX6739MAX6743MAX6744RESETMAX6745VEXTMAX6742MAX6745R1PFIR2PFOR4PFO4.7kΩRESETµPGNDGNDGNDVGOOD = DESIRED VEXT GOOD VOLTAGE THRESHOLDVFAIL = DESIRED VEXT FAIL VOLTAGE THRESHOLDVOH = VCC1 (FOR PUSH-PULL PFO)R2 = 200kΩ (FOR > 2.5µA R2 CURRENT)R1 = R2 ((VGOOD - VTH-PFI) - (VTH-PFI)(VGOOD - VFAIL) / VPU) / VTH-PFIR3 = (R1 x VOH) / (VGOOD - VFAIL)Figure 5. Interfacing to µPs with Bidirectional Reset I/O12Figure 6. Adding Hysteresis to Power Fail for Push-Pull

PFO______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsThe MAX6741/MAX6744 offer a VCC1 POK (POK1) idealTransient Immunityfor VThe MAX6736–MAX6745 supervisors are relativelylong as VCC1-to-V1 is below its VCC2 sequencing. POK1 remains low asCCTH1 threshold. When VCC1immune to short-duration falling Vexceeds Ves). It is usually undesirable to reset the µP when VCCtransients (glitch-open-drain POK1 output is deasserted. The POK1 outputTH1 for the POK1 timeout period (tPOKP), theexperiences only small glitches. The Typical OperatingCCcan then enable the VCharacteristics show Maximum VPOK1 pullup resistor).

CC2 power supply (use an externalRESETis deasserted when bothCC1/VCC2TransientDuration vs. Reset Threshold Overdrive, for which resetVCC1 and VCC2 remain above their selected thresholdspulses are not generated. The graph shows the maxi-for the reset timeout period (tmum pulse width that a falling Vbe used for I/O before core or core before I/O sequenc-RP). The POK1 output canCCtransient might typi-cally have without causing a reset pulse to be , depending on the selected VAs the amplitude of the transient increases, the maxi-See the Typical Application Circuit

CC1/Vand Figure 2 allowable pulse width decreases. A 0.1µF bypassMonitoring a Negative Voltagecapacitor mounted close to the VCCpin provides addi-The power-fail comparator can be used to monitor ational transient ve supply voltage using the circuit shown inFigure 4. When the negative supply is valid, PFOis the negative supply voltage drops, PFOgoesChip Informationhigh. The circuit’s accuracy is affected by the PFITRANSISTOR COUNT: 249threshold tolerance, VCC, R1, and S: BiCMOSFunctional DiagramVCC1MAX6736–MAX6745PFODELAYPOK1VCC1VCC2RSTIN/PFIRESETTIMEOUTRESETPERIODOUTPUTRESETVCC2VCC1MRPULLUP0.488VVCC11.23VMR______________________________________________________________________________________13MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745Selector Guide (continued)PARTMAX6739MAX6740MAX6741MAX6742MAX6743MAX6744MAX6745VOLTAGEMONITORS1 fixed, 1 adj2 fixed, 1 adj2 fixed1 fixed2 fixed, 1adj2 fixed1 fixedOPEN-DRAINRESET—X*X*X*———PUSH-PULLRESETX———XXXMANUALRESETXX*X*X*———POWER-FAILINPUT/OUTPUT———X——XPOKOUTPUT——X——X—RSTININPUTXX——X——*Manual reset detect on

l Application CircuitsDC/DCCONVERTERUNREGULATEDDCINOUTVBATTINOUTDC/DCCONVERTERVCC1VCC2VCC1COREI/OSUPPLYSUPPLYµPINOUTDC/DCCONVERTERSHDNPFOMAX6742VCCµPPFIGNDRESETMAX6741RESETGNDPOK1GNDRESETRESETGNDPUSHBUTTONSWITCHPUSHBUTTONSWITCH14______________________________________________________________________________________

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsPin ConfigurationsTOP VIEWRESET15VCC1RESET15VCC1RESET15VCC1GND2MAX6736MAX6737GND2MAX6738MAX6739GND2MAX6740MAX6743MR34VCC2MR34RSTINRSTIN34VCC2SC70SC70SC70RESET15VCC1RESET15VCC1GND2MAX6741MAX6744GND2MAX6742MAX6745POK134VCC2PFO34PFISC70SC70Ordering Information (continued)PARTTEMP RANGEPIN-PACKAGEMAX6738XK_D_-T*-40°C to +85°C5 SC70-5MAX6739XK_D_-T-40°C to +85°C5 SC70-5MAX6740XK_ _D_-T-40°C to +85°C5 SC70-5MAX6741XK_ _D_-T-40°C to +85°C5 SC70-5MAX6742XK_D_-T-40°C to +85°C5 SC70-5MAX6743XK_ _D_-T*-40°C to +85°C5 SC70-5MAX6744XK_ _D_-T*-40°C to +85°C5 SC70-5MAX6745XK_D_-T-40°C to +85°C5 SC70-5*Future product—contact factory for availability.______________________________________________________________________________________15MAX6736–MAX6745

元器件交易网-Power Dual-/Triple-Voltage SC70 µPSupervisory CircuitsMAX6736–MAX6745Package 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.)SC70,

im cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time.16____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2002 Maxim Integrated Products Printed USAis a registered trademark of Maxim Integrated Products.