TCA8424

Low-Voltage 8x16 Keyboard Scanner With HID over I2C Compliant Interface datasheet

Document overview

• Manufacturer or author: Texas Instruments, Incorporated [SCDS341,*]
• PDF pages: 31

Technical content

0.30 0.18 0.10 M C A B 0.50 3.504X 32X 0.50 0.30 TCA8424 www.ti.com SCDS341 –MARCH 2013 Low-Voltage8x16KeyboardScannerwithHIDoverI2CCompliantInterface Check forSamples: TCA8424 1FEATURES

• OperatingPower-Supply VoltageRange of • ESD ProtectionExceeds JESD 22 1.65Vto3.6V – 1000-V Human-Body Model (A114-A)
• Supports FM+ I2C Operationup to1MHz
• Can Support up to128 (8x16)Key Scan RHB 5mmx5mm RSM 4mmx4mm• InternalPower-On-Reset PREVIEW
• Open DrainOpen DrainActiveLow INT Output
• Noise Filteron SCL/SDA and Inputs
• Open DrainOutputs Can Sink up to12mA CurrentforLED
• Hardware Coded HID and REPORT Descriptors
• AvailableWith Preprogrammed Keyboard Map
• SoftwareReset per HID Over I2C Standard
• InternalPull-upResistorsMake ImplementationEasy With no Need for ExternalComponents
• HID Over I2C Commands Supported – RESET RHA 6mm x 6mm– GET REPORT – SET REPORT – SET POWER
• FixedLength 8-byteINPUT Report can Detect up to6 Simultaneous Key Presses Excluding Modifiers(CTRL, ALT, SHIFT)
• INPUT Report Generated on Key Press and Release
• Latch-Up Performance Exceeds 100 mA Per JESD 78,Class II

DESCRIPTION

This 128 key scan deviceisspecificallytargetedtowardsend equipment thatruns on Windows 8 operating system.The deviceisfullycompliantwiththeHID overI2C specificationdefined(ver1.0)definedby Microsoft. The HID and reportdescriptorsare hard coded intothe deviceso thattheydon’t need to be programmed at production.The devicealsocomes witha preprogrammed keyboardmap thatiscompatiblewithmost standard laptop/notebookkeyboards.However,thedevicealsoavailablewithouta pre-programmedkeyboard,so thatany keyboardmap may be writtenintoitatproduction. The devicegeneratesINPUT reportsofstandard8-bytelengthwiththe1stbytebeingthemodifierbyte.Afterthe keyboardmap isprogrammed intothedeviceitautomaticallyrecognizestherow/columnlocationofthemodifier keys based on theirusage code.Itiscapableofdetectingand reportingup tosixsimultaneouskey pressesplus eightmodifiers.Itgeneratesan inputreporton each key pressand each key release. The devicealsosupportsLED indicatorsthatare standardon a keyboard.Differentvariationssupport2,4or 8 LED outputs.Each outputhas open drainarchitectureand iscapableofsinkingup to12mA ofcurrent.The LEDs arecontrolledby a standardOUTPUT reportas describedintheHID overI2C standard. Pleasebe aware thatan importantnoticeconcerningavailability,standardwarranty,and use incriticalapplicationsof Texas Instrumentssemiconductorproductsand disclaimerstheretoappearsattheend ofthisdatasheet. PRODUCTION DATA informationiscurrentas ofpublicationdate. Copyright© 2013,Texas InstrumentsIncorporatedProductsconform to specificationsper the terms of the Texas Instrumentsstandardwarranty.Productionprocessingdoes not necessarilyincludetestingofallparameters.

ROW0 ROW1 ROW2 ROW3 ROW4 ROW5 ROW6 ROW7 ROW8 ROW9 ROW10 ROW1 1 ROW12 ROW13 COL0 TEST COL7 COL6 COL5 COL4 COL3 COL2 COL1 VCC ROW14 GND ROW15 LED0 LED1 SDA SCL 9 10 1 1 13 12 14 15 17 252629 28 2731 30 RSM/RHB TCA8424 SCDS341 –MARCH 2013 www.ti.com These deviceshave limitedbuilt-inESD protection.The leadsshouldbe shortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamage totheMOS gates. TOP THROUGH VIEW

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(NC) ROW15 LED0 SDA LED1 LED2 LED3 GND (NC) COL1 COL0 ROW13 ROW12 ROW1 1 ROW10 ROW9 ROW6 ROW8 ROW7 COL2ROW14 COL3COL4COL5COL7COL6TESTDVCCDVCC (NC) ROW0ROW1ROW2 ROW5ROW3ROW4 (NC)SCL INT TCA8424 www.ti.com SCDS341 –MARCH 2013 TOP THROUGH VIEW PIN FUNCTIONS NAME TYPE FUNCTION Supplyvoltageforthedevice.The I2C bus shouldbe pulledup tothisrail.The key matrixIO voltagesareVCC Power alsoreferencedtothissupplyvoltage. COL0 –COL7 Input COLs ofthekey matrix ROW0 –ROW15 Output ROW ofkey matrix LED0 –LED7 Output Open drainoutputfordrivingLEDs TEST Input Highvoltageinputused toprogramtheinternalmemory. To be groundedinapplication.(1) GND Power Ground INT output Active-lowinterruptoutput.ConnecttoVCC througha pull-upresistor. SCL Input Serialclockbus.ConnecttoVCC througha pull-upresistor. SDA I/O Serialdatabus.ConnecttoVCC througha pull-upresistor. (1) TEST pinmust be groundedinapplicationtoensureproperoperationofdevice. Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:TCA8424

(volatile) HID Descriptor (30 bytes) Report Descriptor (194 bytes) Keyboard map (256 bytes) Report Ids Usage Codes Function Key Location (32 bytes) Input Register (8 bytes) Output Register (1 bytes) Command Register (2 bytes) Data Register (2 bytes) Key scan Logic Core Logic and internal registers I C buffers and Logic LEDs Interrupt SDA SCL Columns 0 - 7 Rows 0 - 15 TCA8424 SCDS341 –MARCH 2013 www.ti.com SIMPLIFIED BLOCK DIAGRAM I2C INTERFACE The bidirectionalI2C bus consistsof the serialclock(SCL) and serialdata (SDA) lines.Both linesmust be connectedtoVCC througha pull-upresistor.Data transfermay be initiatedonlywhen thebus isnotbusy. I2C communicationwiththisdeviceisinitiatedby a mastersendinga Startcondition,a high-to-lowtransitionon theSDA input/output,whiletheSCL inputishigh.AftertheStartcondition,thedeviceaddressbyteissent,most significantbit(MSB) first,includingthedatadirectionbit(R/W). Afterreceivingthe validaddress byte,thisdeviceresponds withan acknowledge (ACK), a low on the SDA input/outputduringthehighoftheACK-relatedclockpulse. On theI2C bus,onlyone databitistransferredduringeach clockpulse.The dataon theSDA linemust remain stableduringthehighpulseoftheclockperiod,as changes inthedatalineatthistimeareinterpretedas control commands (StartorStop).A Stop condition,a low-to-hightransitionon theSDA input/outputwhiletheSCL input ishigh,issentby themaster. Any number of data bytescan be transferredfrom the transmitterto receiverbetween the Startand the Stop conditions.Each byteofeightbitsisfollowedby one ACK bit.The transmittermust releasetheSDA linebefore thereceivercan send an ACK bit.The devicethatacknowledgesmust pulldown theSDA lineduringtheACK clockpulse,so thattheSDA lineisstablelow duringthehighpulseoftheACK-relatedclockperiod.When a slavereceiverisaddressed,itmust generatean ACK aftereach byteisreceived.Similarly,the master must generatean ACK aftereach bytethatitreceivesfromtheslavetransmitter.Setup and holdtimesmust be met to ensureproperoperation.

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S Clock Pulse for Acknowledgment SDA SCL Data Line Change SDA SCL S P Start Condition Stop Condition TCA8424 www.ti.com SCDS341 –MARCH 2013 A masterreceiversignalsan end ofdatatotheslavetransmitterby notgeneratingan acknowledge(NACK) after thelastbytehas been clockedoutoftheslave.Thisisdone by themasterreceiverby holdingtheSDA linehigh. Inthisevent,thetransmittermust releasethedatalinetoenablethemastertogeneratea Stopcondition. NOTE Any communicationtoanotherdeviceon thesame I2C BUS must be terminatedby a stop conditionbeforecommunicatingto the TCA8424. Any glitchesbelow 0.7 × VCC on the SCL orSDA lineshouldbe lessthan50 ns as pertheI2C specification. Figure1. DefinitionofStartand Stop Conditions Figure2. BitTransfer Figure3. Acknowledgment on I2C Bus DEVICE I2C ADDRESS The addressofthedeviceisshown below: Table1.Address Reference SLAVE ADDRESS I2C BUS SLAVE ADDRESS B7 B6 B5 B4 B3 B2 B1 B0 0 1 1 1 0 1 1 0 (W) 134 (decimal),76(h) 0 1 1 1 0 1 1 1 (R) 135 (decimal),77(h) Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:TCA8424

SCDS341 –MARCH 2013 www.ti.com The lastbitoftheslaveaddressdefinestheoperation(readorwrite)tobe performed.A high(1)selectsa read operation.Whilea low(0)selectsa writeoperation. OtherI2C addressoptionsareavailable.PleasecontactyourlocalTIsalespersonfordeviceswithalternateI2C address. REGISTER ADDRESS BYTE FollowingthesuccessfulacknowledgmentoftheI2C addressbyte,thebus mastersends two registeraddress bytesindicatingthe addressof the registeron which the read or writeoperationneeds to be performed.This registeraddressisstoredinan internalregisterand used by thedeviceforsubsequentread/writetothedevice. Thisisexplainedmore indetailinsubsequentsectionsoftheDS. Other I2C address optionsare available.Contactyour localTI salesperson fordeviceswithalternateI2C address. Table2.RegisterMap REGISTER ADDRESS DESCRIPTION POWER UP DEFAULT(Hex) HID descriptor 0000h-001Dh HID descriptor See sectionon HID descriptor ReportDescriptor 0030h-00F1h Reportdescriptor See sectionon Reportdescriptor KeyboardMap 0100h-01FFh keyboardMap see sectionon Keyboardmap FunctionKey location(1) 0201h FunctionKey locationon KeyboardMap (2) 0 DefaultReportID 0202h DefaultReportID 1 ReportID1 0203h ReportID1 2 ReportID2 0204h ReportID2 3 ReportID3 0205h ReportID3 4 ReportID4 0206h ReportID4 5 ReportID1 usage IDs 0207h-020Eh Usage IDsassociatedwithReportID1 A7 – AE ReportID2 usage IDs 020Fh-0216h Usage IDsassociatedwithReportID2 AF – B6 ReportID3 usage IDs 0217h-021Eh Usage IDsassociatedwithReportID3 B7 – BA ReportID4 usage IDs 021Fh-0226h Usage IDsassociatedwithReportID4 BB – BE 0400h inputreportlength(LSB) 00h 0401h inputreportlength(MSB) 00h 0402h ReportID A2 0403h modifierbyte 00h 0404h reserved reserved Inputreport 0405h usage code 1 00h 0406h usage code 2 00h 0407h usage code 3 00h 0408h usage code 4 00h 0409h usage code 5 00h 040Ah usage code 6 00h Outputreport 0500h LED status 00h 0600h HID overI2C Command lowbyte 00h Command register 0601h HID overI2C Command highbyte 00h Data register 0700-070Ah Data forHID overI2C command 00h (1) FunctionKey Usage ID inkeyboardmap must be non-zero (2) Column/Row intersectionoffunctionkey.i.e.col3row4 intersectionwouldread34h

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www.ti.com SCDS341 –MARCH 2013 Table2.RegisterMap (continued) REGISTER ADDRESS DESCRIPTION POWER UP DEFAULT(Hex) 0000h(3) HID Descriptorlength 40h 0001h 41h 0002h BCD version 42h 0003h 43h 0004h Reportdescriptorlength 44h 0005h 45h 0006h ReportDescriptorRegisteraddress 46h 0007h 47h 0008h Inputregisteraddress 48h 0009h 49h 000Ah max inputreportlength(including2 bytes 4Ah lengthfield)000Bh 4Bh 000Ch Outputregisteraddress 4Ch 000Dh 4Dh 000Eh max outputreportlength(including2 bytes 4Eh HID Descriptor(3) lengthfield)000Fh 4Fh(0000h-001Dh) 0010h Command registeraddress 50h 0011h 51h 0012h dataregisteraddress 52h 0013h 53h 0014h Vendor ID 54h 0015h 55h 0016h ProductID 56h 0017h 57h 0018h VersionID 58h 0019h 59h 001Ah ReservedperHID overI2C spec v0.91 5Ah 001Bh 5Bh 001Ch 5Ch 001Dh 5Dh 5Eh (3) The Hid descriptorstartaddress must be 0000h Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:TCA8424

(HID Desc Addr - LSB) SrData (HID Desc Addr - MSB) Address Ack Ack R Ack Ack Nak PData HID Desc - LSB Data HID Desc - MSB SDA driven by HOST (Direction: HOST to DEVICE) SDA driven by DEVICE (Direction: DEVICE to HOST) LEGEND S – Start; P – Stop; Sr – Repeated Start R – Read(1); W – Write(0) Ack – Acknowledgment Nak – Negative Acknowledgment TCA8424 SCDS341 –MARCH 2013 www.ti.com HID DESCRIPTOR RETRIEVAL Figure4. TypicalRetrievaloftheHID Descriptor Figure4 shows thetypicalretrievaloftheHID descriptor.Thisisthemost common way theHID descriptoris retrieved.However,theTCA8424 allowspartialretrievalofthedescriptoras describedintheHID overI2C spec rev1.0. Table3.Report Descriptor RegisterAddress Power up Default 30 5F 31 60 32 61 33 62 34 63 35 64 36 65 37 66 38 67 39 68 3A 69 3B 6A Report(1)descriptor 3C 6B(0030h-00F1h) 3D 6C 3E 6D 3F 6E 40 6F 41 70 42 71 43 72 44 73 45 74 46 75 47 76 48 77 (1) Reportdescriptorcontentsmay varydependingon versionofdevice.PleasecontactTIfordevicefor differentReportDescriptorcontents

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www.ti.com SCDS341 –MARCH 2013 Table3.Report Descriptor(continued) RegisterAddress Power up Default Reportdescriptor 49 78 (0030h-00F1h) 4A 79 4B 7A 4C 7B 4D 7C 4E 7D 4F 7E 50 7F 51 80 52 81 53 82 54 83 55 84 56 85 57 86 58 87 59 88 5A 89 5B 8A 5C 8B 5D 8C 5E 8D 5F 8E 60 8F 61 90 62 91 63 92 64 93 65 94 66 95 67 96 68 97 69 98 6A 99 6B 9A 6C 9B 6D 9C 6E 9D 6F 9E 70 9F 71 A0 72 A1 73 A2 74 A3 75 A4 76 A5 Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:TCA8424

SCDS341 –MARCH 2013 www.ti.com Table3.Report Descriptor(continued) RegisterAddress Power up Default Reportdescriptor 77 A6 (0030h-00F1h) 78 A7 79 A8 7A A9 7B AA 7C AB 7D AC 7E AD 7F AE 80 AF 81 B0 82 B1 83 B2 84 B3 85 B4 86 B5 87 B6 88 B7 89 B8 8A B9 8B BA 8C BB 8D BC 8E BD 8F BE 90 BF 91 C0 92 C1 93 C2 94 C3 95 C4 96 C5 97 C6 98 C7 99 C8 9A C9 9B CA 9C CB 9D CC 9E CD 9F CE A0 CF A1 D0 A2 D1 A3 D2 A4 D3 A5 D4

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www.ti.com SCDS341 –MARCH 2013 Table3.Report Descriptor(continued) RegisterAddress Power up Default Reportdescriptor A6 D5 (0030h-00F1h) A7 D6 A8 D7 A9 D8 AA D9 AB DA AC DB AD DC AE DD AF DE B0 DF B1 E0 B2 E1 B3 E2 B4 E3 B5 E4 B6 E5 B7 E6 B8 E7 B9 E8 BA E9 BB EA BC EB BD EC BE ED BF EE C0 EF C1 F0 C2 F1 C3 F2 C4 F3 C5 F4 C6 F5 C7 F6 C8 F7 C9 F8 CA F9 CB FA CC FB CD FC CE FD CF FE D0 FF D1 0 D2 1 D3 2 D4 3 Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLinks:TCA8424

(Report Desc Reg - LSB) SrData (Report Desc Addr - MSB) Address Ack Ack R Ack Ack Nak P Data (Report Desc - LSB) Data (Report Desc - MSB) SDA driven by HOST (Direction: HOST to DEVICE) SDA driven by DEVICE (Direction: DEVICE to HOST) LEGEND S – Start; P – Stop; Sr – Repeated Start R – Read(1); W – Write(0) Ack – Acknowledgment Nak – Negative Acknowledgment TCA8424 SCDS341 –MARCH 2013 www.ti.com Table3.Report Descriptor(continued) RegisterAddress Power up Default Reportdescriptor D5 4 (0030h-00F1h) D6 5 D7 6 D8 7 D9 8 DA 9 DB 0A DC 0B DD 0C DE 0D DF 0E E0 0F E1 10 E2 11 E3 12 E4 13 E5 14 E6 15 E7 16 E8 17 E9 18 EA 19 EB 1A EC 1B ED 1C EE 1D EF 1E F0 1F REPORT DESCRIPTOR RETREIVAL

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www.ti.com SCDS341 –MARCH 2013 INPUT REPORT Inputreportsareused tocommunicate key pressesand releasestothehostcontroller.The TCA8424 iscapable ofcommunicatingup tosixsimultaneouskey pressesand up toeightmodifierkeys.The standardmodifierkeys recognizedby theTCA8424 are(Usage ID based on HID usage tablesver1.11).The usage ID foreach key is storedinthekeyboardmap sectionofNV memory.

• LeftCtrl(Usage ID – E0)
• Leftshift(Usage ID – E1)
• LeftAlt(Usage ID – E2)
• LeftGUI (Usage ID – E3)
• RightCtrl(Usage ID – E4)
• Rightshift(Usage ID – E5)
• RightAlt(Usage ID – E6)
• RightGUI (Usage ID – E7) Below isthatformatofa standardinputreport.The firsttwo bytesare datalengthfieldindicatingthelengthof inputreport. Byte Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 0 0 0 0 0 1 0 1 1 1 0 0 0 0 0 0 0 0

2 ReportID

3 RightGUI RightAlt RightShift RightCtrl LeftGUI LeftAlt LeftShift LeftCtrl

4 Reserved

5 Key1 Usage ID

6 Key2 Usage ID

7 Key3 Usage ID

8 Key4 Usage ID

9 Key5 Usage ID

10 Key6 Usage ID

An inputreportisgeneratedforeverykey pressand alsoon everykey release.Ifno keys are pressedaftera key releasethenthereportcontainsallzeroesexceptfortheData lengthfield(firsttwo bytes)and theReportID. Inputreportsarealsogeneratedifonlymodifierkeys arepressed(notaccompanied by any otherkey).The data lengthfield(firsttwo bytes)fora standardkey pressisalways11. SPECIAL MODIFIER (Fn key)AND ALTERNATE REPORT IDs Otherthanthestandardmodifiers,theTCA8424 alsosupportsone specialmodifiersuch as thefunction(FN) key.Thisoperatesdifferentfromtheothermodifierkeys inthat,itisnotrepresentedinthemodifierbyteofthe inputreport.The TCA8424 onlysupportsa singlekey pressincombinationwiththeFN key. When theFN key ispressedtheTCA8424 generatesa defaultinputreportindicatingthatallkeys have been released.A FN key releasewillgeneratean inputreportwiththecurrentReportID and clearedusage codes. The TCA8424 onlysupportsa singlekey pressincombinationwiththeFN key.Any key pressedaftertheFN key thatdoes nothave a non-zeroUsage ID willbe ignored.Once theFN key ispressedand a key thathas an Usage ID inthealternatekeyboardmap has been pressed,additionalkey presseswillbe ignoreduntileitherthe FN key isreleasedorthesecond key thathad an Usage ID inthealternatekeyboardmap isreleased. In additionto standardfunctionkeys,many keyboardssupportspecialfunctionssuch as volume up, volume down, skiptrack,previoustracketc.ReportIDs areused as a way forthehostprocessortoidentifywhetherthe usage ID correspondstoa standardfunctionkey ora specialfunctionkey.The TCA8424 supportsFivedifferent reportIDs.Report IDs must be non-zero. 1. DefaultReportID – locatedataddress0202h.ThisID ispopulatedintheinputreportwhen thereisa normal key pressora regularfunctionkey. 2. ReportID 1 – locatedataddress0203h.ThisID ispopulatedinthereportwhen theUsage ID ofthekey pressdetectedby theTCA8424 correspondstoa usage ID locatedinthememory range(0207h-020Eh) 3. ReportID 2 – locatedataddress0204h.ThisID ispopulatedinthereportwhen theUsage ID ofthekey Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLinks:TCA8424

(Length Field - LSB) Data (Length Field - MSB) SDA driven by HOST (Direction: HOST to DEVICE) SDA driven by DEVICE (Direction: DEVICE to HOST) LEGEND S – Start; P – Stop; Sr – Repeated Start R – Read(1); W – Write(0) Ack – Acknowledgment Nak – Negative Acknowledgment Data (Report Field - LSB) Ack NakData (Report Field - MSB) P TCA8424 SCDS341 –MARCH 2013 www.ti.com pressdetectedby theTCA8424 correspondstoa usage ID locatedinthememory range(020Fh-0216h) 4. ReportID 3 – locatedataddress0204h.ThisID ispopulatedinthereportwhen theUsage ID ofthekey pressdetectedby theTCA8424 correspondstoa usage ID locatedinthememory range(0217h-021Eh) 5. ReportID 4 – locatedataddress0204h.ThisID ispopulatedinthereportwhen theUsage ID ofthekey pressdetectedby theTCA8424 correspondstoa usage ID locatedinthememory range(021Fh-0226h) As can be inferredfrom the above description,whenever a key pressisdetected,the TCA8424 looksup the usage ID fromthealternatekeyboardmap and thencompares thisusage ID withtheusage IDscorrespondingto ReportID 1, ReportID 2, ReportID 3, and ReportID 4. Ifthereisa match,then correspondingreportID is populatedinthespecialinputreport.Ifnotthedefaultinputreportisused withthedefaultReportID.(1) Below isthe formatof the specialinputreport.The formatissimilarto the bitfieldrepresentationused to representthe modifierbyteinthe standardinputreport.Usage ID bytelocation0 willcorrespondto the first Usage ID inmemory fortherespectiveReportID (2)and descend withUsage ID bytelocation7 correspondingto thelastUsage ID inmemory.(2) Table4.SpecialInputReport Byte Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 0 Usage ID Usage ID Usage ID Usage ID Usage ID Usage ID Usage ID Usage ID 3 bytelocation bytelocation bytelocation bytelocation bytelocationbytelocation2bytelocation1bytelocation 7 6 5 4 3 0 (1) The last5 key Usage IDsintheinputreportand themodifierbytewillalwaysread00h when thefunctionkey ispressedinadditionto anotherkey. (2) ForReportID1:Usage ID bytelocation0 correspondstomemory location0207h.Usage ID bytelocation7 correspondstomemory location020Eh. Figure5. InputReport Retrieval Itisimportanttonotethat,unlikeretrievalofotherreports,where thefirstI2C transactionisa write,inthecase of inputreportthefirsttransactionitselfisa readoperationas indicatedby Bit8 oftheI2C address.

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(Output Register - LSB) Data ( - MSB)Output Register SDA driven by HOST (Direction: HOST to DEVICE) SDA driven by DEVICE (Direction: DEVICE to HOST) LEGEND S – Start; P – Stop; Sr – Repeated Start R – Read(1); W – Write(0) Ack – Acknowledgment Nak – Negative Acknowledgment Data (Report Field - LSB) Ack Data (Report Field - MSB) P Data (Length Field - LSB) Ack Data (Length Field - MSB) Ack Ack TCA8424 www.ti.com SCDS341 –MARCH 2013 OUTPUT REPORT Outputreportsare used by the hostto turnON/OFF any indicatorLEDs ( caps lock,num locketc.)on the keyboard.The TCA8424 can supportfrom2 to4 LED indicatorsdependingon theversionofthedevicechosen. The outputreportsaresinglebytereports(8-bit)where each bitindicatesthestatusofthecorrespondingLED. A ‘1’indicatesthattheLED isturnedon where as a ‘0’turnsofftheLED. Below istheformatoftheoutputreport receivedfromthehost.Justas inthecase oftheinputreportthefirsttwo bytesindicatethelengthoftheoutput report. Byte Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0

2 Reserved Reserved Reserved Reserved LED3 LED2 LED1 LED0

Figure6. Output Report Retrieval COMMAND and DATA REGISTER The HID overI2C spec requiresthatalldevicesrespondtocertaincommands. The commands areissuedtothe command register.The command isan opcode as definedby the HID over I2C spec.The operand forthe command goes tothedataregister.Below isa listofcommands supportedby theTCA8424. Op Code Command Name Effecton Device Deviceisresetand allregistersarereturnedtodefaultvalue.Thiscommand has thesame effecton the0001b RESET deviceas a power on reset. 0010b GET_REPORT Most recentinputreportistransferredtoData Register 0011b SET_REPORT Data registercontentsareused toturnon/offLED. 1000b SET_POWER AllLEDs areturnedoffand deviceisinlowestcurrentmode (willstilldetectkey presses) The I2C transactionsused toissuethesecommands areexactlyas describedintheHID overI2C standard. RESET AfterreceivingtheRESET command, thedevicewillgo througha fullpower on resetand allregistersareloaded withtheirdefaultvalues.The TCA8424 takes~600µs toresetand duringthistimeallI2C trafficwillbe ignoredby thedevice.Aftercoming outofreset,thedatalengthfieldintheinputreportispopulatedwith0000h and theINT signalisasserted. GET_REPORT The GET_REPORT command willretrievethecurrentinputreportfromthedevicebutwillnotcleartheinterrupt assertedfroma key pressorrelease. Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLinks:TCA8424

SCDS341 –MARCH 2013 www.ti.com SET_REPORT The SET_REPORT command isused tosetthecontentsoftheoutputreport.The Data shallbe packaged with thelengthfieldas 0x0003,and thethirdbyteshalldescribetheLED outputsas definedinthereportdescriptor. SET_POWER The SET_POWER=SLEEP command willturnoffalltheLED outputsand cleartheinputreportincludingreport ID and lengthfield.Ifa key ispressedwhen SET_POWER=SLEEP command isreceived,keyscan willstop when thecommand isreceived.TCA8424 willwaitforallkeys tobe releasedbeforeany subsequentkey press willassertan interrupt.Ifa key ispressedand notreleasedwhiledeviceisasleepand theSET_POWER=WAKE command isreceived,the key scanner willstartand assertan interruptthata key has been pressed.The SET_POWER=WAKE command isreceivedtheLED outputswillbe returnedtothestatetheywere beforethe SET_POWER=SLEEP was received.Ifa command to change the outputreportisreceivedduringsleep,the LED statuswillindicatethatofthelastoutputreportreceivedupon SET_POWER=WAKE. Ifkeys are pressed whilethe device is enteringsleep mode, a read of the inputreportor use of the GET_REPORT command beforeallkeysarereleased,may notreflectthecurrentstateofthekeyboard.Any key pressesthathappen afterallkeysarereleasedwillpopulatetheinputreportand assertINT. KEYBOARD MAP The Non volatilememory containsa sectionthatcontainsthekeyboardmap. Each bytelocationinthekeyboard map, ismapped toa specificrow column intersectionon thekey matrix,and containstheusage ID ofthekey locatedin thatrow column intersection.The keyboard map consistsof two sections.Each row column intersectionismapped toone locationineach section.The primarysectioncontainstheusage ID ofthekey and thealternatesectioncontainsthealternateusage ID ofthekey thatwillbe reportedwhen thespecialmodifier (FN)isused.Onlykeyswithnon-zerousage codes willbe recognized,includingthefunctionkey. The deviceisavailablewithsome pre definedkeyboardmaps. Itisalsoavailablewiththe keyboardmap not programmed so thatthe end user may program the keyboard map based on the keyboard being used. Alternatelyyou may contactTI forcustom variationsof the partwithdifferentkeyboardmaps programmed by specialrequest. The tablebelowillustratesthecolumn-rowintersectionsand thememory locationstheyaremapped to. KEYBOARD MAP (PRIMARY) KEYBOARD MAP (SECONDARY) C0 C1 C2 C3 C4 C5 C6 C7 C0 C1 C2 C3 C4 C5 C6 C7 R0 A1 B1 C1 D1 E1 F1 81 91 R0 A1 B1 C1 D1 E1 F1 81 91 R1 A2 B2 C2 D2 E2 F2 82 92 R1 A2 B2 C2 D2 E2 F2 82 92 R2 A3 B3 C3 D3 E3 F3 83 93 R2 A3 B3 C3 D3 E3 F3 83 93 R3 A4 B4 C4 D4 E4 F4 84 94 R3 A4 B4 C4 D4 E4 F4 84 94 R4 A5 B5 C5 D5 E5 F5 85 95 R4 A5 B5 C5 D5 E5 F5 85 95 R5 A6 B6 C6 D6 E6 F6 86 96 R5 A6 B6 C6 D6 E6 F6 86 96 R6 A7 B7 C7 D7 E7 F7 87 97 R6 A7 B7 C7 D7 E7 F7 87 97 R7 A8 B8 C8 D8 E8 F8 88 98 R7 A8 B8 C8 D8 E8 F8 88 98 R8 A9 B9 C9 D9 E9 F9 89 99 R8 A9 B9 C9 D9 E9 F9 89 99 R9 AA BA CA DA EA FA 8A 9A R9 AA BA CA DA EA FA 8A 9A R10 AB BB CB DB EB FB 8B 9B R10 AB BB CB DB EB FB 8B 9B R11 AC BC CC DC EC FC 8C 9C R11 AC BC CC DC EC FC 8C 9C R12 AD BD CD DD ED FD 8D 9D R12 AD BD CD DD ED FD 8D 9D R13 AE BE CE DE EE FE 8E 9E R13 AE BE CE DE EE FE 8E 9E R14 AF BF CF DF EF FF 8F 9F R14 AF BF CF DF EF FF 8F 9F R15 B0 C0 D0 E0 F0 80 90 A0 R15 B0 C0 D0 E0 F0 80 90 A0

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www.ti.com SCDS341 –MARCH 2013 KEYSCAN LOGIC FunctionalOverview Upon power up orwhen coming outofRESET, thedevicesinitializesitselfwithalltheregistershavingthepower up defaultvalue.Allthe COLx pinsare pulledup to VCC by internalpullup resistors.Allthe ROWx pinsare pulledlow.The deviceisnow inidle/standbymode (lowestpower state).When any key ispressed,one ofthe COL pinsgetsconnectedtoone oftheROW pins,therebypullingdown thecorrespondingCOL pin.Thisinitiates thekeyscan. When thisoccurs the internaloscillatorturnson, and each ROWx pin goes low,one afterthe other,for approximately800uS whiletheCOLx inputsaresampled ateach step.Then, foreverykey thatispressed,the correspondingusage ID fromthekeyboardmap isregistered.Afterapproximately25mS, thescan willrepeat.If any previouslypressedkey isstillpressed,thenthecorrespondingcode iswrittentotheInputregister.The scan continuestorepeatas longas therearekeys pressed.Now, when a previouslypressedkey isreleasedanother inputreportisgeneratedwiththekeys thatarestillpressed,orifno keys arepressed,thenan inputreportwith allzeroUsage codes isreported. Once theinputreporthas been populatedintotheinputregister,theINT isassertedtoindicatetothehostthat an inputreportisnow available. Interrupt(INT)Output An interruptisgeneratedwhen thedevicehas an inputreportreadyfortheHOST toread.Resettingtheinterrupt isachievedby readingtheINPUT Register.UsingtheGET_REPORT command willnotcleartheinterrupt.The interruptwillclearafterthe2nd read byteoftheempty inputreporton reset.Afterreset,a defaultinputreport readwillcleartheinputreportafterthelastbyteisread.Ifa specialinputreportisread,theinterruptclearsafter the4th byteisread. The interruptstatusisupdated inthe read mode at the acknowledge (ACK) or not acknowledge (NACK) bit followingthe risingedge of the SCL signalafterthe lastbyteof the inputreporthas been read.The INPUT registerwillkeep gettingupdated withthe most recentkey press reportseven whilethe INT signalstays asserted.In orderavoidmissingof key pressesitisrecommended thathost processorrespond to interrupt servicerequestin<50ms (debouncetime) The INT outputhas an open-drainstructureand requiresa pull-upresistortoVCC .When thedevicecomes outof power on reset,the /INTsignalisassertedto indicateto the hostthatthe devicehas come out of reset(as requiredby theHID overI2C).The valueinthedatalengthfieldoftheinputreportissetto0000h when the devicecomes outofPOR (asrequiredby theHID overI2C). Power-On Reset When power (from0V) isappliedtoVCCP ,an internalpower-onresetholdstheTCA8424 ina resetconditionuntil VCCP has reachedVPOR .At thattime,theresetconditionisreleased,and theTCA8424 registersand I2C state machine initializeto theirdefaultstates.Afterthat,VCCP must be loweredto below VPORF and back up to the operatingvoltagefora power-resetcycle.

• Duringpower up,ifVCCI ramps beforeVCCP ,a power on reseteventoccursand theI2C registersarereset.
• IfVCCP ramps up beforeVCCI,thenthedevicewithresetas ifRESET = 0
• The deviceisresetregardlessofwhichVCCx ramps first. Power-On Reset Requirements Intheeventofa glitchordatacorruption,TCA8424 can be resettoitsdefaultconditionsby usingthepower-on resetfeature.Power-on resetrequiresthatthe devicego througha power cycleto be completelyreset.This resetalsohappens when thedeviceispowered on forthefirsttimeinan application. The two typesofpower-onresetareshown inFigure7 and Figure8. Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 17 ProductFolderLinks:TCA8424

tTRR_VPOR50 V drops below POR levelsIN tRT VCC Time tFT tRT Ramp-Up Ramp-Down Re-Ramp-Up tTRR_GND TCA8424 SCDS341 –MARCH 2013 www.ti.com Figure7. VCC isLowered Below 0.2V or 0 V and Then Ramped Up toVCC Figure8. VCC isLowered Below thePOR Threshold,Then Ramped Back Up toVCC Glitchesinthepower supplycan alsoaffectthepower-onresetperformanceofthisdevice.The glitchwidth(tGW ) and height(tGH ) are dependent on each other.The bypass capacitance,source impedance, and device impedance are factorsthataffectpower-on resetperformance.Figure9 providesmore informationon how to measure thesespecifications. Figure9. GlitchWidth and GlitchHeight VPOR iscriticaltothepower-onreset.VPOR isthevoltagelevelatwhichtheresetconditionisreleasedand allthe registersand theI2C/SMBus statemachine areinitializedtotheirdefaultstates.The valueofVPOR differsbased on theVCC beingloweredtoorfrom0.Figure10 providesmore detailson thisspecification. Figure10. VPOR

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www.ti.com SCDS341 –MARCH 2013 The tablebelow specifiestheperformanceofthepower-onresetfeatureforTCA8424 forbothtypesofpower-on reset. RECOMMENDED SUPPLY SEQUENCING AND RAMP RATES AT TA = 25°C (1) overoperatingfree-airtemperaturerange(unlessotherwisenoted) PARAMETER MIN TYP MAX UNIT tFT Fallrate 1 100 ms tRT Riserate 0.1 100 ms tRR_GND Time tore-ramp(when VCC dropstoGND) 40 μs tRR_POR50 Time tore-ramp(when VCC dropstoVPOR_MIN – 50 mV) 40 μs LevelthatVCCP can glitchdown to,butnotcause a functionaldisruptionwhenVCC_GH 1.2 VVCCX_GW = 1 μs tGW Glitchwidththatwillnotcause a functionaldisruptionwhen VCCX_GH = 0.5× VCCx 10 μs VPORF VoltagetrippointofPOR on fallingVCC 0.86 1.22 V VPORR VoltagetrippointofPOR on risingVCC 1.1 1.34 V (1) Not tested.Specifiedby design ABSOLUTE MAXIMUM RATINGS (1)(2) overoperatingfree-airtemperaturerange(unlessotherwisenoted) MIN MAX UNIT VCCI Supplyvoltagerange –0.3 4 V VI Inputvoltagerange –0.3 4 V VILED InputvoltagerangeLED outputs –0.3 5.5 V VITEST Inputvoltagerangetestpin 7.7 V IIK Inputclamp current SCL VI< 0 ±10 mA IOK Outputclamp current INT VO < 0 ±10 mA IIOK Input/outputclamp current SDA VO < 0 orVO > VCC ±10 mA SDA VO = 0 ±30 mA ContinuousoutputlowIOL INT VO = 0 ±10 mAcurrent LEDx VO = 0 ±20 mA Tstg Storagetemperaturerange –65 150 °C (1) Stressesbeyond thoselistedunder“absolutemaximum ratings”may cause permanentdamage tothedevice.These arestressratings only,and functionaloperationofthedeviceattheseorany otherconditionsbeyond thoseindicatedunder“recommended operating conditions”isnotimplied.Exposuretoabsolute-maximum-ratedconditionsforextendedperiodsmay affectdevicereliability. (2) The inputnegative-voltageand outputvoltageratingsmay be exceeded iftheinputand outputcurrentratingsareobserved. Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 19 ProductFolderLinks:TCA8424

SCDS341 –MARCH 2013 www.ti.com RECOMMENDED OPERATING CONDITIONS overoperatingfree-airtemperaturerange(unlessotherwisenoted) MIN MAX UNIT VCCI Supplyvoltage 1.65 3.6 V Vtest Voltageon testpin Duringnormaloperation(inapplication) GND GND V VILED Voltageon LED output 5 V VIH High-levelinputvoltage SCL, SDA 0.7× VCCI 3.6 V VIL Low-levelinputvoltage SCL, SDA –0.3 0.3× VCCI V SDA 20 mA Low-leveloutputIOL INT 3 mAcurrent LEDx 12 mA TA Operatingfree-airtemperature –40 85 °C

ELECTRICAL CHARACTERISTICS

Allvaluesarespecifiedat25°C operatingtemperature(unlessotherwisenoted) PARAMETER TEST CONDITIONS VCC MIN TYP MAX UNIT VIK Inputdiodeclamp voltage II= –18 mA 1.65V to3.6V –1.2 V 1.65V 0.4 1.8V 0.4 ROWx, INT IOL = 3 mA 2.5V 0.4 V 3.3V 0.4 3.6V 0.4 VOL 1.65V 0.4 1.8V 0.4 SDA IOL = 20 mA 2.5V 0.4 V 3.3V 0.4 3.6V 0.4 1.8V 0.4 V VOL LEDx IOL = 12 mA 3.3V 0.4 5 V 0.4 IOL LEDx VOL = 0.4V 1.65V – 5.5V 12 mA R int Internalpullup resistance 80 100 120 kΩ 1.65V 0.25 8 1.8V 0.27 8 Iccsh0 Currentconsumption Fscl= 0 kHz,oscillatoroff 2.5V 0.4 12 µA 3.3V 0.54 16 3.6V 0.6 20 1.65V 17 18 1.8V 18 20 Icc4khz1 Currentconsumption Fscl= 400 kHz,oscillatoron 2.5V 25 30 µA 3.3V 33 40 3.6V 39 50 1.65V 36 40 1.8V 39 50 Icc1Mhz1 Currentconsumption Fscl= 1 MHz, oscillatoron 2.5V 48 60 µA 3.3V 65 70 3.6V 60 80 ΔIcc Incrementalcurrentfordurationofkey press One key pressed 1.65V – 3.6V 39 45 µA Cin SCL, SDA 5 10 pF

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www.ti.com SCDS341 –MARCH 2013 I2C INTERFACE TIMING REQUIREMENTS overoperatingfree-airtemperaturerange(unlessotherwisenoted) STANDARD FAST MODEFAST MODEMODE PLUS (FM+)I2C BUSPARAMETER UNITI2C BUS I2C BUS MIN MAX MIN MAX MIN MAX fscl I2C clockfrequency 0 100 0 400 0 1000 kHz tsch I2C clockhightime 4 0.6 0.26 μs tscl I2C clocklowtime 4.7 1.3 0.5 μs tsp I2C spiketime 50 50 50 ns tsds I2C serialdatasetuptime 250 100 50 ns tsdh I2C serialdataholdtime 0 0 0 ns ticr I2C inputrisetime 1000 20 300 120 ns 20 x (VDD / 20 x (VDD /ticf I2C inputfalltime 300 300 120 ns5.5V) 5.5V) 20 x (VDD / 20 x (VDD /tocf I2C outputfalltime;10 pF to400 pF bus 300 300 120 μs5.5V) 5.5V) tbuf I2C bus freetimebetween Stopand Start 4.7 1.3 0.5 μs tsts I2C StartorrepeaterStartconditionsetuptime 4.7 0.6 0.26 μs tsth I2C StartorrepeaterStartconditionholdtime 4 0.6 0.26 μs tsps I2C Stopconditionsetuptime 4 0.6 0.26 μs tvd(data) Validdatatime;SCL lowtoSDA outputvalid 3.45 0.3 0.9 0.45 μs ValiddatatimeofACK condition;ACK signalfromSCLtvd(ack) 3.45 0.3 0.9 0.45 μslowtoSDA (out)low SWITCHING CHARACTERISTICS overoperatingfree-airtemperaturerange(unlessotherwisenoted) PARAMETER FROM (INPUT) TO (OUTPUT) MIN MAX UNIT tir Interruptresetdelaytime SCL INT 600 ns tpv Outputdatavalid SCL LEDx 155 ns Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 21 ProductFolderLinks:TCA8424

R = 2.2kL Ω DUT INT C = 25 pF (see note A) L INTERRUPT LOAD CONFIGURATION VCCI R = 1kL Ω DUT SDASDA C = 50 pF (see note A) L SDA LOAD CONFIGURATION Stop Condition (P) Start Condition (S) Address Bit 7 (MSB) Address Bit 1 Bit 0 (LSB) W ACK (A) Data Bit 7 (MSB) Data Bit 0 (LSB) Stop Condition (p) Two Bytes for READ Input Report (see Figure 5) SDA SCL tbuf ticf tsth ticr tsds ticf ticr tschtscl tsp tsdh tvd(ack) tocf tvd tvd tsps tsts 0.7 x VCCI 0.3 x VCCI 0.7 x VCCI 0.3 x VCCI Repeat Start Condition Stop ConditionVOLTAGE WAVEFORMS TCA8424 SCDS341 –MARCH 2013 www.ti.com PARAMETER MEASUREMENT INFORMATION A. C L includesprobe and jigcapacitance.tocf ismeasured withC L of 10 pF or 400 pF. Allinputsare suppliedby generatorshaving the followingcharacteristics:PRR ≤ 10 MHz, ZO = 50 Ω, tr/tf ≤ 30 ns. Allparametersand waveformsarenotapplicabletoalldevices. Figure11. I2C InterfaceLoad Circuitand VoltageWaveforms A. C L includesprobeand jigcapacitance.Allinputsaresuppliedby generatorshavingthefollowingcharacteristics:PRR ≤ 10 MHz, ZO = 50 Ω,tr/tf≤ 30 ns.Allparametersand waveformsarenotapplicabletoalldevices. Figure12. InterruptLoad Circuitand VoltageWaveforms

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0.5 Vcci

R = 420L Ω DUT LED tIR tPV TCA8424 www.ti.com SCDS341 –MARCH 2013 PARAMETER MEASUREMENT INFORMATION (continued) Figure13. LED Load Configuration Figure14. Row Pull-downLoad Configuration C L includesprobeand jigcapacitance.tpv ismeasured from0.7× VCC on SCL to50% I/O(Pn)output.Allinputs are suppliedby generatorshavingthe followingcharacteristics:PRR ≤ 10 MHz, ZO = 50 Ω, tr/tf ≤ 30 ns.The outputsaremeasured one ata time,withone transitionpermeasurement.Allparametersand waveformsarenot applicabletoalldevices. Copyright© 2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 23 ProductFolderLinks:TCA8424

www.ti.com 11-Nov-2025 PACKAGING INFORMATION Orderable part number Status (1) Material type (2) Package | Pins Package qty | Carrier RoHS (3) Lead finish/ Ball material (4) MSL rating/ Peak reflow (5) Op temp (°C) Part marking (6) TCA8424RHAR NRND Production VQFN (RHA) | 40 2500 | LARGE T&R Yes NIPDAU Level-3-260C-168 HR -40 to 85 PZ 424 TCA8424RHAR.A NRND Production VQFN (RHA) | 40 2500 | LARGE T&R Yes NIPDAU Level-3-260C-168 HR -40 to 85 PZ 424 (1) Status: For more details on status, see our product life cycle. (2) Material type: When designated, preproduction parts are prototypes/experimental devices, and are not yet approved or released for full production. Testing and final process, including without limitation quality assurance, reliability performance testing, and/or process qualification, may not yet be complete, and this item is subject to further changes or possible discontinuation. If available for ordering, purchases will be subject to an additional waiver at checkout, and are intended for early internal evaluation purposes only. These items are sold without warranties of any kind. (3) RoHS values: Yes, No, RoHS Exempt. See the TI RoHS Statement for additional information and value definition. (4) Lead finish/Ball material: Parts may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two lines if the finish value exceeds the maximum column width. (5) MSL rating/Peak reflow: The moisture sensitivity level ratings and peak solder (reflow) temperatures. In the event that a part has multiple moisture sensitivity ratings, only the lowest level per JEDEC standards is shown. Refer to the shipping label for the actual reflow temperature that will be used to mount the part to the printed circuit board. (6) Part marking: There may be an additional marking, which relates to the logo, the lot trace code information, or the environmental category of the part. Multiple part markings will be inside parentheses. Only one part marking contained in parentheses and separated by a "~" will appear on a part. If a line is indented then it is a continuation of the previous line and the two combined represent the entire part marking for that device. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 1

*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Reel Diameter (mm) Reel Width W1 (mm) (mm) (mm) (mm) (mm) W (mm) Pin1 Quadrant PACKAGE MATERIALS INFORMATION www.ti.com 29-Sep-2019 Pack Materials-Page 1

*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) TCA8424RHAR VQFN RHA 40 2500 367.0 367.0 38.0 PACKAGE MATERIALS INFORMATION www.ti.com 29-Sep-2019 Pack Materials-Page 2

www.ti.com GENERIC PACKAGE VIEW This image is a representation of the package family, actual package may vary. Refer to the product data sheet for package details. VQFN - 1 mm max heightRHA 40 PLASTIC QUAD FLATPACK - NO LEAD6 x 6, 0.5 mm pitch 4225870/A

www.ti.com PACKAGE OUTLINE 6.15 5.85 6.15 5.85 1.0 0.80.05 0.00 2X 4.5 36X 0.5 2X 4.5 40X 0.5 0.3 40X 0.30 0.18 2.62 0.1 3.52 0.1 (0.1) TYP VQFN - 1 mm max heightRHA0040E PLASTIC QUAD FLATPACK - NO LEAD 4219054/A 04/2020 0.08 C

0.1 C A B

0.05 NOTES: 1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing per ASME Y14.5M. 2. This drawing is subject to change without notice. 3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance. PIN 1 INDEX AREA SEATING PLANE PIN 1 ID SYMMEXPOSED THERMAL PAD SYMM 11 20 3140 SCALE 2.000 AB C

www.ti.com EXAMPLE BOARD LAYOUT 36X (0.5) (R0.05) TYP

0.07 MAX

0.07 MIN

40X (0.6) 40X (0.24) (5.8) (5.8) (2.62) (3.52) ( 0.2) TYP VIA (0.6) TYP (0.91) (1.06) VQFN - 1 mm max heightRHA0040E PLASTIC QUAD FLATPACK - NO LEAD 4219054/A 04/2020 NOTES: (continued) 4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature number SLUA271 (www.ti.com/lit/slua271). 5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown on this view. It is recommended that vias under paste be filled, plugged or tented. SYMM SYMM LAND PATTERN EXAMPLE EXPOSED METAL SHOWN SCALE: 15X SEE SOLDER MASK DETAIL 11 20 3140 METAL EDGE SOLDER MASK OPENING EXPOSED METAL METAL UNDER SOLDER MASK SOLDER MASK OPENING EXPOSED METAL NON SOLDER MASK DEFINED (PREFERRED) SOLDER MASK DEFINED SOLDER MASK DETAILS

www.ti.com EXAMPLE STENCIL DESIGN 40X (0.6) 40X (0.24) 36X (0.5) (5.8) (5.8) 6X (1.15) 6X (1) (R0.05) TYP (0.675) (1.2) VQFN - 1 mm max heightRHA0040E PLASTIC QUAD FLATPACK - NO LEAD 4219054/A 04/2020 NOTES: (continued) 6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate design recommendations. SOLDER PASTE EXAMPLE BASED ON 0.125 MM THICK STENCIL SCALE: 15X EXPOSED PAD 41 75% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE SYMM SYMM 11 20 3140

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