74HC595:8ChannelShiftRegisterwith3StateOutputforHighSpeedDigitalLogic

TableofContents

1.Overview

2.Features

3.Applications

4.PinConfiguration

5.FunctionalDescription

6.TruthTable

7.TimingDiagrams

8.AbsoluteMaximumRatings

9.ElectricalCharacteristics

10.PackageInformation

1.Overview

2.Features

8bitserialinputandoutput

3stateoutputsforbusorientedapplications

Cascadableforlongershiftregisters

Highspeedoperation

Lowpowerconsumption

Availableinawiderangeofpackages

3.Applications

Serialtoparalleldataconversion

Shiftregisteroperations

Storageregisterfunctions

LEDandLCDdisplaydrivers

Generalpurposelogicapplications

Microprocessorperipheralcontrol

4.PinConfiguration

The74HC595hasa16pinDIP/SOPpackagewiththefollowingpinconfiguration:

1.Q0OutputBit0

2.Q1OutputBit1

3.Q2OutputBit2

4.Q3OutputBit3

5.Q4OutputBit4

6.Q5OutputBit5

7.Q6OutputBit6

8.Q7OutputBit7

9.MRMasterReset(ActiveLow)

10.SH_CPShiftRegisterClockInput

11.ST_CPStorageRegisterClockInput

12.OEOutputEnable(ActiveLow)

13.DSSerialDataInput

14.Q7'CascadingOutput(SerialOutput)

15.VCCPositiveSupplyVoltage

16.GNDGround

5.FunctionalDescription

The74HC595operatesshiftingdataintotheshiftregisterandthentransferringittothestorageregister.The3stateoutputscanbeenabledordisabledasneeded.Thedevicecanbecascadedtocreatelongershiftregisters.Here'sabriefdescriptionofitsoperation:

DataisshiftedintotheshiftregisterontherisingedgeoftheSH_CPclockinput.

ThedataintheshiftregisteristransferredtothestorageregisterontherisingedgeoftheST_CPclockinput.

TheoutputsareenabledwhenOEislowanddisabledwhenOEishigh.

TheMRinputresetstheshiftregisterandstorageregistertoallzeroswhenlow.

TheDSinputistheserialdatainputfortheshiftregister.

TheQ7'outputallowscascadingofmultiple74HC595devicesforlongershiftregisters.

6.TruthTable

Tobetterunderstandthebehaviorofthe74HC595,thefollowingtruthtableoutlinestheoperationofthedevicebasedontheinputconditions:

|MR|OE|SH_CP|ST_CP|DS|Q0|Q1|Q2|Q3|Q4|Q5|Q6|Q7|Q7'|

|||||||||||||||

|H|H|X|X|X|H|H|H|H|H|H|H|H|H|

|H|L|X|X|X|Q0|Q1|Q2|Q3|Q4|Q5|Q6|Q7|Q7|

|L|X|X|X|X|L|L|L|L|L|L|L|L|L|

|H|L|↑|X|L|Q0|Q1|Q2|Q3|Q4|Q5|Q6|Q7|L|

|H|L|X|↑|X|Q0'|Q1'|Q2'|Q3'|Q4'|Q5'|Q6'|Q7'|Q7'|

Note:'H'representsahighlogiclevel,'L'representsalowlogiclevel,'X'indicatestheinputisirrelevant,'↑'indicatesapositiveedge,and'Qx'and'Qx''representthepreviousandnewstatesoftheoutputs,respectively.

7.TimingDiagrams

Thetimingdiagramsforthe74HC595illustratetherelationshipbetweentheclockinputsandthedataflowthroughthedevice.Propertimingiscrucialforthedevicetofunctioncorrectly.

ShiftRegisterClock(SH_CP):ThedataatDSisloadedintotheshiftregisterontherisingedgeofSH_CP.

StorageRegisterClock(ST_CP):ThedatafromtheshiftregisteristransferredtothestorageregisterontherisingedgeofST_CP.

OutputEnable(OE):TheoutputsareenabledwhenOEislowanddisabledwhenOEishigh,regardlessoftheclocksignals.

8.AbsoluteMaximumRatings

Exceedingthesemaximumratingscancausepermanentdamagetothedevice.Theseratingsarestressratingsonly,andfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedintheoperationalsectionsofthisspecificationisnotimplied.

SupplyVoltage(VCC):0.5Vto+7V

InputVoltage(VIN):0.5VtoVCC+0.5V

OutputVoltage(VOUT):0.5VtoVCC+0.5V

OperatingTemperature:40°Cto+125°C

StorageTemperature:65°Cto+150°C

OutputCurrent(IOUT):±35mA

PowerDissipation(PD):500mW

9.ElectricalCharacteristics

Thefollowingelectricalcharacteristicsareguaranteedunderthespecifiedoperatingconditions:

SupplyVoltage(VCC):2Vto6V

InputHighVoltage(VIH):VCC0.3V

InputLowVoltage(VIL):0.3V

OutputHighVoltage(VOH):VCC0.3V(IOH=6mA)

OutputLowVoltage(VOL):0.3V(IOL=6mA)

InputLeakageCurrent(IIN):±1μA

OutputLeakageCurrent(IOUT):±1μA

propagationDelay(tpd):50ns(VCC=5V)

10.PackageInformation

The74HC595isavailableinvariouspackages,includingthepopular16pinDualInlinePackage(DIP)andSmallOutlinePackage(SOP).Thepackagedimensionsandpinoutareasfollows:

DIPPackage:600milwidth,300milpitch

SOPPackage:150milwidth,300milpitch

Ensurethatthepackagechosenissuitablefortheapplicationandthatproperthermalmanagementisconsideredforhighpowerorhightemperatureenvironments.

11.OrderingInformation

74HC595N:DIPpackage

74HC595D:SOPpackage

74HC595PW:TSSOPpackage

74HC595M:SOICpackage

Makesuretocheckwithyoursupplierforavailabilityandanyadditionalpackageoptionsthatmaybeoffered.

12.HandlingPrecautions

Toensurethereliabilityandperformanceofthe74HC595,pleaseadheretothefollowinghandlingprecautions:

Avoidstaticdischargeusingantistaticwriststrapsandworkingonstaticsafesurfaces.

Donotexposethedevicetomoistureorcorrosivegases.

Handlethedeviceitsedgestopreventdamagetothepins.

Donotbendthepinsexcessivelywheninsertingorremovingthedevicefromasocket.

Useappropriatesolderingtechniquesandtemperaturestopreventheatdamage.

13.MountingConsiderations

Propermountingiscrucialforthe74HC595tofunctionoptimally.Herearesomeconsiderationsformountingthedevice:

EnsurethatthePCBtracesaredesignedtohandletheexpectedcurrentandthattheydonotexceedthemaximumoutputcurrentratings.

KeeptheVCCandGNDtracesasshortaspossibletominimizenoiseandinductance.

UsedecouplingcapacitorsclosetotheVCCandGNDpinstostabilizethepowersupplyandreduceelectricalnoise.

Ifusingasocket,ensureitisthecorrecttypeforthepackageandthatitissecurelymountedtothePCB.

14.TypicalApplications

The74HC595findsitswayintoamultitudeofapplicationsduetoitsversatility.Herearesometypicalusecases:

LEDMatrixControl:Drivean8x8LEDmatrixoraseriesofLEDdisplaysusingmultiple74HC595stocontroltherowsandcolumns.

LCDSegmentDrivers:DrivethesegmentlinesofLCDdisplayswiththe74HC595,allowingfordynamicdisplayupdates.

ShiftRegisterExpansion:ExpandtheI/Ocapabilitiesofmicrocontrollerscascadingmultiple74HC595stocontrolalargenumberofoutputswithjustafewmicrocontrollerpins.

DigitalClock:Buildadigitalclockusingthe74HC595todrivethedigitsofasevensegmentdisplay.

15.Troubleshooting

Ifyouencounterissueswiththe74HC595,con