LM8207 TI1 | Alldatasheet
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& LDO TIMING CONTROL VCOM REFERENCE VREF GAMMA CORRECTION CURVE LM8207
18 GAMMA BUFFER VCOM
www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 LM8207TFT18GammaBuffer+VCOM Driver+VoltageReference Check forSamples: LM8207 1FEATURES DESCRIPTION The LM8207 isa combinationof18-channelgamma 2• Gamma Buffers1-2Swing toVDD buffers, a VCOM driver and a temperature• Gamma Buffers17-18Swing toVSS compensated internalvoltage reference.It is
- Large Output CurrentVCOM Driver designedforbufferingvoltagelevelsand drivinghigh (ISC = 300 mA) capacitiveloads in largeTFT panels.The gamma buffersare individuallyoptimizedto the input/output• Stable(1%) Internal1.295VReference,to requirementsof theirrespectivegamma positiontoImprove PictureQualityand Reduce Variations coverthe whole voltagerange from railto rail.Any• 48-pinTSSOP Package desiredgamma correctioncurvecan be obtainedby combiningthegamma bufferswithexternalresistors. APPLICATIONS The VCOM driverhas a highoutputcurrentcapability and isstablewithlargecapacitiveloads,typicalfor• TFT Gamma Curve Connection and VCOM largepanelsizes.Thiswillresultina fastrecoveryVoltageBuffering time forlargevoltagevariationsat the output.The internalband gap referencecan be used to form a highly stable voltage to generate the gamma correctionvoltages.In combinationwiththe internal amplifier,the referencevoltagecan be programmed to voltagesup to the positiverail.The LM8207 is offeredina 48-pinTSSOP package. TFT Panel Block Diagram Pleasebe aware thatan importantnoticeconcerningavailability,standardwarranty,and use incriticalapplicationsof Texas Instrumentssemiconductorproductsand disclaimerstheretoappearsattheend ofthisdatasheet. 2Alltrademarksarethepropertyoftheirrespectiveowners. PRODUCTION DATA informationiscurrentas ofpublicationdate. Copyright© 2005–2013,Texas InstrumentsIncorporatedProductsconform to specificationsper the terms of the Texas Instrumentsstandardwarranty.Productionprocessingdoes not necessarilyincludetestingofallparameters.
SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com These deviceshave limitedbuilt-inESD protection.The leadsshouldbe shortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamage totheMOS gates. AbsoluteMaximum Ratings(1)(2) Human Body 2.5kV ESD Tolerance(3) Machine Model 250V SupplyVoltage(VDD -VSS ) 18V StorageTemperatureRange −65°C to+150°C JunctionTemperature(4) +150°C SolderingInformation InfraredorConvection(20sec.) 230°C Wave Soldering(10sec.) 260°C (1) AbsoluteMaximum Ratingsindicatelimitsbeyond whichdamage tothedevicemay occur.OperatingRatingsindicateconditionsfor whichthedeviceisintendedtobe functional,butspecificperformanceisnotensured.Forensuredspecifications,see theElectrical Characteristicstables. (2) When theoutputoftheVCOM bufferexceedsthesupplyrails,whilesinkingorsourcing100 mA, theVCOM outputissusceptibletolatch. (3) Human body model,1.5kΩ inserieswith100 pF.Machine model,0Ω inserieswith200 pF (4) The maximum power dissipationisa functionofTJ(MAX),θJA and TA.The maximum allowablepower dissipationatany ambient temperatureisPD = (TJ(MAX) – TA)/θJA.Allnumbers applyforpackagessoldereddirectlyontoa PC board. OperatingRatings(1) OperatingTemperatureRange −40°C to+105°C OperatingVoltageRange 6V to16V Package ThermalResistance,θJA (2) 48-PinTSSOP 84°C/W (1) AbsoluteMaximum Ratingsindicatelimitsbeyond whichdamage tothedevicemay occur.OperatingRatingsindicateconditionsfor whichthedeviceisintendedtobe functional,butspecificperformanceisnotensured.Forensuredspecifications,see theElectrical Characteristicstables. (2) The maximum power dissipationisa functionofTJ(MAX),θJA and TA.The maximum allowablepower dissipationatany ambient temperatureisPD = (TJ(MAX) – TA)/θJA.Allnumbers applyforpackagessoldereddirectlyontoa PC board.
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www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 16V ElectricalCharacteristics(1) Unlessotherwisespecified,alllimitsensuredforTJ = 25°C, VDD = 16V,VSS = 0V,& C LOAD = 100 pF (Gamma & VCOM Buffers). Boldfacelimitsapplyatthetemperatureextremes. Symbol Parameter Conditions Min (2) Typ (3) Max (2) Units Gamma Buffers BW_Gamma −3 dB Bandwidth 2 MHz SR_Gamma Slew Rate(4) 1 V/µs TREC _Gamma OutputRecoveryTime(5) 400 ns VIN_Gamma InputVoltageRange Buffer1-2 Positive VDD Negative VSS +0.6 Buffer3-8& 11-16 Positive VDD -0.6 Negative VSS +0.6 Buffer9 Positive VDD −0.6 V Negative VSS Buffer10 Positive VDD -0.6 Negative VSS +0.6 Buffer17-18 Positive VDD −0.6 Negative VSS VOUT _Gamma OutputVoltageRange Buffer1-2, Positive VDD -0.25 VDD -0.1 No Load Negative VSS +1.5 VSS +1.6 Buffer3-8& 11-16 Positive VDD −1.2 VDD -1.1 No Load Negative VSS +0.6 VSS +0.7 Buffer9, Positive VDD −1.0 VDD -0.8 VNo Load Negative VSS +0.8 VSS +0.9 Buffer10, Positive VDD –1.2 VDD –1.1 No Load Negative VSS +0.6 VSS +0.7 Buffer17-18, Positive VDD –1.6 VDD –1.5 No Load Negative VSS +0.1 VSS +0.25 IBIAS_Gamma Absolute,InputBiasCurrent WithinGamma BufferOutput 30 nAVoltageRange VOS _Gamma InputOffsetVoltage Buffer1-2,VIN = 8V 5 10 Buffer3-8,11-16,VIN = 8V 1 5 Buffer9,VIN = 8V 1 5 mV Buffer10,VIN = 8V 1 5 Buffer17-18,VIN = 8V 5 10 (1) ElectricalTablevaluesapplyonlyforfactorytestingconditionsatthetemperatureindicated.Factorytestingconditionresultinvery limitedself-heatingofthedevicesuch thatTJ = TA.No specificationofparametricperformanceisindicatedintheelectricaltableunder conditionsofinternalself-heatingwhere TJ > TA. (2) Alllimitsarespecifiedby designorstatisticalanalysis. (3) Typicalvaluesrepresenttheparametricnorm atthetimeofcharacterization. (4) Slew Rate ismeasured forVIN = 4 VPP .10% -90% valuesareused.Slew rateistheaverageoftherisingand fallingslewrates (5) 4 VPP pulse(50ns risetime)appliedtoone sideof100 pF seriesoutputcapacitance,othersideconnectedtooutputofbuffer.Outputto within0.1% ofinputvoltage. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:LM8207
SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com 16V ElectricalCharacteristics(1)(continued) Unlessotherwisespecified,alllimitsensuredforTJ = 25°C, VDD = 16V,VSS = 0V,& C LOAD = 100 pF (Gamma & VCOM Buffers). Boldfacelimitsapplyatthetemperatureextremes. Symbol Parameter Conditions Min (2) Typ (3) Max (2) Units IOUT _Gamma LinearOutputCurrent(6) Buffer1-2 Sourcing 20 46 Sinking 0.2 0.33 Buffer3-8& 11-16 Sourcing 10 24.5 Sinking 3.5 5.5 Buffer9 Sourcing 4.5 9.4 mA Sinking 15 27 Buffer10 Sourcing 23 34.8 Sinking 3.5 5.5 Buffer17-18 Sourcing 0.2 0.33 Sinking 20 50 PSRR Power SupplyRejectionRatio VDD -VSS = 6V to16V 75 88 dB VCOM Driver BW_V COM Bandwidth 10 MHz SR_ VCOM Slew Rate(4) 4.5 V/μs T_REC _VCOM OutputRecoveryTime(5) 200 ns VIN_VCOM InputVoltageRange Positive VDD V Negative VSS +0.6 VOUT _VCOM OutputVoltageRange No Load Positive VDD –1.0 VDD –0.7 V Negative VSS +0.9 VSS +1.2 IBIAS_VCOM InputBiasCurrent WithinVCOM BufferOutput 50 nAVoltageRange VOS _VCOM InputOffsetVoltage VIN = 8 V 1 10 mV IOUT _LIN_VCOM LinearOutputCurrent(6)(7) Sourcing 160 mA Sinking 150 IOUT _SC_V COM ShortCircuitOutputCurrent(7)(8) Sourcing 220 300 mA Sinking 220 300 PSRR Power SupplyRejectionRatio VDD -VSS = 6V to16V 75 88 dB VoltageReferenceSection VREF Voltage No Load 1.28 1.295 1.31 V Reg LOAD Load Regulation IOUT = 0 to10 mA 0.14 mV/mA VREF_ACC VoltageAccuracy No Load,VREF = 1.295V 1 % VREF_MAX Max Programming Range IOUT = 4 mA VDD −0.3 V InputBiasCurrent WithinVREF OutputVoltageIIN_VREF 10 50 nARange TC_V REF TemperatureStability 70 ppm/°C IOUT _VREF Max OutputCurrent Sourcing,VOUT = 1.295V 71 mA PSRR Power SupplyRejectionRatio 70 80 dB(LineRegulation) Miscellaneous IS SupplyCurrent 4.5 6.5 8.5 mA9.5 (6) Linearoutputcurrentmeasured at|VOUT -VIN|= 0.1V. (7) Thisisa momentary test.Continuouslargeoutputcurrentsmay resultinexceedingthemaximum power dissipationand damage the device. (8) Shortcircuitcurrentmeasured at|VOUT -VIN|= 1V.
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IN_VREF OUT_3 OUT_2 OUT_1 NC OUT_9 OUT_8 OUT_5 OUT_6 OUT_4 OUT_11 VSS OUT_V COM NC OUT_18 OUT_17 OUT_16 OUT_15 NC OUT_13 OUT_14 OUT_7 OUT_12 OUT_10 OUT_V REF IN_8 IN_VCOM IN_11 IN_18 IN_7 IN_6 IN_9 IN_4 IN_2 NC IN_10 VDD IN_5 IN_1 IN_3 NC NC IN_17 IN_16 IN_15 IN_14 IN_13 IN_12 LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 Connection Diagram Figure1. 48-PinTSSOP Top View PIN DESCRIPTIONS Pin # Description Remark
1 OUT_V REF Referencevoltageamplifieroutput
2 NC No connection
3 IN_1 Inputgamma buffer1
4 IN_2 Inputgamma buffer2
5 IN_3 Inputgamma buffer3
6 IN_4 Inputgamma buffer4
7 IN_5 Inputgamma buffer5
8 IN_6 Inputgamma buffer6
9 IN_7 Inputgamma buffer7
10 IN_8 Inputgamma buffer8
11 IN_9 Inputgamma buffer9
12 VDD Positivesupplyvoltage(VDD )
13 IN_10 Inputgamma buffer10
14 IN_11 Inputgamma buffer11
15 IN_12 Inputgamma buffer12
16 IN_13 Inputgamma buffer13
17 IN_14 Inputgamma buffer14
18 IN_15 Inputgamma buffer15
19 IN_16 Inputgamma buffer16
20 IN_17 Inputgamma buffer17
21 IN_18 Inputgamma buffer18
22,23 NC No connection Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:LM8207
IN_1 IN_2 IN_18 OUT_18 OUT_17 OUT_1 OUT_V COMIN_VCOM IN_17 OUT_2 VREF 1.295V VDD VSS IN_VREF OUT_V REF LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com PIN DESCRIPTIONS (continued)
24 IN_VCOM InputVCOM
25 OUT_V COM OutputVCOM
26,27 NC No connection
28 OUT_18 Outputgamma buffer18
29 OUT_17 Outputgamma buffer17
30 OUT_16 Outputgamma buffer16
31 OUT_15 Outputgamma buffer15
32 OUT_14 Outputgamma buffer14
33 OUT_13 Outputgamma buffer13
34 OUT_12 Outputgamma buffer12
35 OUT_11 Outputgamma buffer11
36 OUT_10 Outputgamma buffer10
37 VSS Negativesupplyvoltage(VSS )
38 OUT_9 Outputgamma buffer9
39 OUT_8 Outputgamma buffer8
40 OUT_7 Outputgamma buffer7
41 OUT_6 Outputgamma buffer6
42 OUT_5 Outputgamma buffer5
43 OUT_4 Outputgamma buffer4
44 OUT_3 Outputgamma buffer3
45 OUT_2 Outputgamma buffer2
46 OUT_1 Outputgamma buffer1
47 NC No connection
48 IN_VREF Referencevoltageamplifierfeedbackinput
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ISOURCING (mA) 0.1 1 10 0.001 0.01 0.1 VOUT FROM V IN (V) -40°C 125°C 85°C 25°C 0.1 1 10 100 ISINKING (mA) 0.001 0.01 0.1 VOUT FROM V IN (V) -40°C 85°C 125°C 25°C 125°C 0.1 1 10 100 1000 ISINKING (mA) 0.001 0.01 0.1 VOUT FROM V IN (V) 125°C 25°C85°C -40°C 0.1 1 10 100 1000 ISOURCING (mA) 0.001 0.01 0.1 VOUT FROM V IN (V) -40°C 85°C 125°C 25°C 0 0.4 0.8 1.2 1.6 0.2 0.4 0.6 0.8 1.2 1.4 1.6 1.8 VOUT (V) VIN (V) GAMMA BUFFER 1-2 GAMMA BUFFER 3-16 GAMMA BUFFER 17-18 VCOM BUFFER 14 14.4 14.8 15.2 15.6 14.2 14.4 14.6 14.8 15.2 15.4 15.6 15.8 VOUT (V) VIN (V) GAMMA BUFFER 1-2 GAMMA BUFFER 3-16 GAMMA BUFFER 17-18 VCOM BUFFER LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 TypicalPerformance Characteristics AtTJ = 25°C, VDD = 16V,VSS = 0V.Unlessotherwisespecified. Output VoltageSwing (Negativerail) Output VoltageSwing (Positiverail) Figure2. Figure3. VoltageDrop vs.Output Current(VCOM Buffer) VoltageDrop vs.Output Current(VCOM Buffer) Figure4. Figure5. VoltageDrop vs.Output Current(Gamma Buffer) VoltageDrop vs.Output Current(Gamma Buffer) Figure6. Figure7. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:LM8207
5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 VOLTAGE (V)
1 Ps/DIV
IN_VCOM OUT_V COM 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 VOLTAGE (V) IN_VCOM OUT_V COM 7.2 7.4 7.6 7.8 8.0 8.2 8.4 8.6 8.8 OUT_V COM TIME 200 ns/DIV VPULSE = 4 VPP TIME 200 ns/DIV 7.2 7.4 7.6 7.8 8.0 8.2 8.4 8.6 8.8 OUT_V COM VPULSE = 4 VPP 8 10 12 14 16 VDD (V) VOS (mV) -40°C 85°C 25°C 125°C 125°C 6 8 10 12 14 16 VOS (mV) VDD (V) -40°C 25°C 85°C LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com TypicalPerformance Characteristics(continued) AtTJ = 25°C, VDD = 16V,VSS = 0V.Unlessotherwisespecified. OffsetVoltagevs.Supply Voltage(Gamma Buffer) OffsetVoltagevs.Supply Voltage(VCOM Buffer) Figure8. Figure9. Recovery Time (VCOM Buffer)NegativeSlope Recovery Time (VCOM Buffer)PositiveSlope (CL = 100 pF) (CL = 100 pF) Figure10. Figure11. Large SignalTransientResponse (VCOM Buffer) Large SignalTransientResponse (VCOM Buffer) NegativeSlope (CL = 100 pF) PositiveSlope (CL = 100 pF) Figure12. Figure13.
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6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 OUT_GAMMA VPULSE = 4 VPP TIME 200 ns/DIV 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 OUT_GAMMA VPULSE = 4 VPP 10k 100k 1M 10M 100M FREQUENCY (Hz) GAIN (dB) -360 -270 -180 -90 PHASE (° )GAIN PHASE 100 1k 10k 100k FREQUENCY (Hz) 100 PSRR (dB) 100k 1M 10M 100M FREQUENCY (Hz) GAIN (dB) -40°C 25°C 85°C105°C 100k 1M 10M 100M FREQUENCY (Hz) GAIN (dB) C L = 100 pF C L = 68 pF C L = 15 pF NO LOAD LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 TypicalPerformance Characteristics(continued) AtTJ = 25°C, VDD = 16V,VSS = 0V.Unlessotherwisespecified. Frequency Response forVariousTemperature Frequency Response forVariousLoad (VCOM Buffer) (VCOM Buffer) Figure14. Figure15. Gain/Phase (Gamma Buffer) (CL = 100 pF) PSRR (VCOM Buffer) Figure16. Figure17. Recovery Time (Gamma Buffer3-16)NegativeSlope Recovery Time (Gamma Buffer3-16)PositiveSlope (CL = 100 pF) (CL = 100 pF) Figure18. Figure19. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:LM8207
GAIN (dB) 10k 100k 1M 10M FREQUENCY (Hz) -360 -270 -180 -90 PHASE (° )GAIN PHASE 100 1k 10k 100k FREQUENCY (Hz) 100 PSRR (dB) GAIN (dB) 100k 1M 10M FREQUENCY (Hz) -40°C 25°C 85°C 105°C FREQUENCY (Hz) 100k 1M 10M GAIN (dB) C L = 100 pF C L = 68 pF C L = 15 pF NO LOAD 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 VOLTAGE (V) IN_GAMMA OUT_GAMMA 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 VOLTAGE (V) IN_GAMMA OUT_GAMMA LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com TypicalPerformance Characteristics(continued) AtTJ = 25°C, VDD = 16V,VSS = 0V.Unlessotherwisespecified. Large SignalTransientResponse (Gamma Buffer3-16) Large SignalTransientResponse (Gamma Buffer3-16) Negativeslope(CL = 100 pF) Positiveslope(CL = 100 pF) Figure20. Figure21. Frequency Response forVariousLoad Frequency Response forVariousTemperature (Gamma Buffer) (Gamma Buffer) Figure22. Figure23. Gain/Phase (Gamma Buffer) (CL = 100 pF) PSRR (Gamma Buffer) Figure24. Figure25.
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VDD (V) 1.27 1.28 1.29 1.30 1.31 1.32 1.33 VREF (V) -40°C 25°C 85°C 125°C 10 100 1k 10k 10k FREQUENCY (Hz) PSRR (dB) 6 8 10 12 14 16 5.2 5.4 5.6 5.8 6.2 6.4 6.6 6.8 IDD (mA) 125°C VDD (V) -40°C 25°C 85°C 0 5 10 15 40 45 50 55 60 ILOAD (mA) 1.28 1.29 1.30 1.31 1.32 1.33 1.34 1.35 1.36 VREF (V) 20 25 30 35 -40°C 25°C 85°C 125°C LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 TypicalPerformance Characteristics(continued) AtTJ = 25°C, VDD = 16V,VSS = 0V.Unlessotherwisespecified. Supply Currentvs.Supply Voltage VoltageReferencevs.Output Current Figure26. Figure27. VoltageReferencePSRR VoltageReferencevs.Supply Voltage (LineRegulation) Figure28. Figure29. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLinks:LM8207
± POLARITY LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com APPLICATION SECTION INTRODUCTION The performancecapabilitiesofTFT-LCD ’s increaserapidly,withconstantimprovementssuch as largersizes, higherresolution,and greaterbrightness.Today’s LCD ’s have screen resolutionsof over 1 Mega pixeland higher.The LM8207 can be used toimprovetheperformanceofan LCD. Itisdesignedforbuffering18 gamma voltagelevelsand drivingthe VCOM level.These voltagelevelscan be derivedfrom a highlystableVoltage Reference,whichisincludedintheLM8207. The LM8207 meets thedesignrequirementsthatcombine technical improvementwiththedemand forcosteffectivesolutions. The followingsectionsdiscusstheprincipleoperationofa TFT-LCD and theprincipleoperationoftheLM8207 which includessectionson each of the following:the VoltageReference,the Gamma Buffers,and the VCOM Buffer.Afterthis,the nextsectionspresenta typicalLM8207 configurationand considerthe maximum power dissipation.The end of thisapplicationsectionintroducesthe evaluationboard and presents layout recommendations. PRINCIPLE OPERATION OF A TFT-LCD Thissectionoffersa briefoverviewof the principleoperatingof TFT-LCD ’s.There isa detaileddescriptionof how informationispresentedon thedisplay.An explanationofhow dataiswrittentothescreenpixelsand how thepixelsareselectedisalsoincluded. Figure30. IndividualLCD Pixel Figure30 shows a simplifiedillustrationofan individualLCD pixel.The topand bottomplatesofa pixelconsistof Indium-TinOxide (ITO),whichisa transparent,electricallyconductivematerial.ITO lieson theinnersurfacesof two glasssubstratesthatare thefrontand back glasspanelsofa TFT display.Sandwiched between two ITO platesisan insulatingmaterial(liquidcrystal).This altersthe polarizationof light,depending on how much voltage(VPIXEL) isappliedacrossthetwo plates.Polarizer’s are placedon theoutersurfacesofthetwo glass substrates.Incombinationwiththeliquidcrystal,thepolarizer’s createa variablelightfilterthatmodulateslight transmittedfromtheback tothefrontofa display.A pixel’s bottomplatelieson thebacksideofa displaywhere a lightsourceisapplied,and thetopplatelieson thefront,facingtheviewer.For most TFT displays,a pixel transmitsthe greatestamount of lightwhen VPIXEL ≤ ±0.5 V, and itbecomes lesstransparentas the voltage increaseswitheithera positiveornegativepolarity. For colordisplays,each pixelisbuiltwiththreeindividualsub pixels.Each sub pixelrepresentsa primarycolor. These colorsare Red, Green and Blue (RGB). Combining thesethreeprimarycolorseveryuser-definedcolor can be created. Figure31 shows a simplifieddiagramofa TFT display,showinghow individualpixelsareconnectedtotherow, column and VCOM driver.Each pixelisrepresentedby a capacitorwitha NMOS transistorconnectedtoitstop plate.Pixelsina TFT panelare arrangedinrows and columns.Row linesare connectedtotheNMOS gates, and column linestotheNMOS sources.The back plateofeverypixelisconnectedtoa common voltagecalled VCOM . The voltageappliedto the top plates(alsocalledgamma voltage)controlsthe pixelbrightness.The
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& LDO TIMING CONTROL VCOM REFERENCE VREF GAMMA CORRECTION CURVE LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 column driverssupplythisgamma voltageviathecolumn lines,and ‘write’thisvoltagetothepixelsone row ata time.Thisisaccomplishedby havingtherow driversselectingan individualrow ofpixelswhen thecolumn driver writesthegamma voltagelevels.The row driverssequentiallyapplya largepositivepulse(typically25V to35V) toeach row line.Thisturnson theNMOS transistorsconnectedtoan individualrow,allowingvoltagefrom the column linestobe writtentothepixels. Figure31. TFT Display The VCOM driver(buffer)suppliesa common voltage(VCOM )toallthepixelsina TFT panel.VCOM isa constant DC voltagethatisinthemiddleofthegamma voltagerange.As a result,when a column driverwritestoa row of pixels,theappliedvoltagesareeitherpositiveornegativewithrespecttoVCOM .Infact,thepolarityofa pixelis reversedeach timea row isselected,preventinga patternfrombeing‘burned’intotheLCD. Figure32. Block Diagram ofa TypicalTFT-LCD Figure32 shows how the displayinformationisrefreshed.Using the row and column drivers,one pixelis addressed at the display.The column driverreceivesthe digitalcolordata from the timingcontroller.The correspondinggamma voltagewillbe determined,using the gamma correctioncurve.In fact,the gamma correctioncurveisjusta voltagereferencewith18 outputtabs,which presetsthecolorintensitysettings.This gamma voltageiswrittentothepixel.The column driverselectsone column atthetime;thechangingintheload may affectthe‘tabs’ofthegamma correctioncurve.Thisproblemcan be solvedusing‘gamma buffers’toisolate thegamma correctioncurvefromthecolumn driver. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLinks:LM8207
OUT_V REF = 1.295 x ¨ R 1 + R2 R 2 OUT_V REF = 1.295 x ¨ R 1 + R2 R 2 + R1 x IIN_VREF LM8207 OUT_V REF IN_VREF R 1 R 2 1.295V VREF + IIN_VREF LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com PRINCIPLE OPERATION oftheLM8207 The LM8207 combinesthreebasicfunctionsused inTFT displays:
- VoltageReference – To improve picturequalityand to reduce brightnessvariations,a highlystablereferencevoltageis available.Ithas a low driftovertheoperationtemperaturerange.Thisoutputvoltage(OUT_V REF )isused as thereferencevoltagetodefinethegamma correctionvalues.
- Gamma Buffers – The gamma correctioncurve can be definedeasilyusingan externalchainof precisionresistors.To ensure load independentgamma correctionlevels,18 gamma buffers,each having a low output resistance,can be used todrivetheTFT displaycolumn drivers.
- VCOM Buffer – The VCOM buffersuppliesa common voltage,which isappliedtotheback plateofallthepixels.Writing colorinformationtoallthepixelswillcause highcurrentvariationsattheVCOM levelso thisVCOM bufferis designedfordrivinglargeoutputcurrents. These threefunctionsarediscussedindetailinthefollowingsections. VOLTAGE REFERENCE The internalVoltageReferenceoftheLM8207 can be used toimprovepicturestability.Thisaccuratereference ishighlystableovertheoperationtemperaturerange.The outputvoltage(OUT_V REF )oftheVoltageReference can be setusingtwo externalresistors.Inthenexttwo sections,thepossibilitiesforsettingtheoutputvoltageof theVoltageReferenceand theoperatingrangeoftheVoltageReferencearediscussed. SETTING THE OUTPUT VOLTAGE OF THE VOLTAGE REFERENCE The outputvoltageof the VoltageReferenceAmplifier(OUT_V REF ) can be setusingthe internalreferencein combinationwiththeinternalamplifierand two externalresistors.InFigure33 a typicalapplicationcircuitforVREF isgiven. Figure33. TypicalApplicationCircuitforVREF To calculatetheoutputvoltageoftheVoltageReferenceAmplifier(OUT_V REF )use thefollowingequation: (1) As can be seen inthe16V ElectricalCharacteristicstable,IIN_VREF has a typicalvalueof−10 nA. Using resistor valuesforR 1 = 9 kΩ and R 2 = 1 kΩ thisresultsina gainof 10 and OUT_V REF = 12.95 V an errorwillbe introducedof −10 nA*9 kΩ = −90 μV. Thiserrorcan be neglected.The simplifiedformulaforcalculatingthe OUT_V REF is: (2)
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OUT_V REF IN_VREF R 1 R 2 1.295V ILOAD VREF + ILOAD 1.295V 16V OUT_V REF OPERATING OUTPUT VOLTAGE RANGE HEADROOM IOUT_V REF LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 Example: VDD = 16V OUT_V REF = 14.4V Choose R 2 = 5 kΩ.UsingEquation2,thiswillresultinR 1 = 50.6kΩ THE OPERATING RANGE OF THE VOLTAGE REFERENCE The outputof the VoltageReferenceAmplifierhas a minimum of 1.295V (R1 = 0).Thisisdeterminedby the valueoftheinternalreference.The maximum outputvoltage(OUT_V REFMAX ) can approachthepositivesupply railVDD .The voltageislimitedby theoutputresistance(ROUT ) oftheoutputstageoftheinternalamplifierand depends on theloadcurrent.Figure34 shows theoperatingoutputvoltagerange. Figure34. OperatingOutput VoltageRange The minimum headroom (OUT_V REF withrespecttothepositivesupplyrailVDD )can be measured usingthetest circuitshown inFigure35. Figure35. Headroom TestCircuitwithVariableOutput CurrentLoad The headroom is measured by varyingboth the supplyvoltageand the outputcurrent(ILOAD ) fora fixed programmed value of OUT_V REF . As shown in Figure36, the minimum headroom slightlyincreasesfora constantVDD when theloadcurrentincreases. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLinks:LM8207
0 32 64 96 128 160 192 224 256 INPUT (DIGITAL VALUE) VGMA3 VGMA12 VGMA1 VGMA18 VCOM VGMA16 VGMA14 VGMA5 VGMA7 0 2 4 6 8 10 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 HEADROOM (V) ILOAD (mA) LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com Figure36. VoltageReferenceHeadroom vs.Load Current GAMMA BUFFERS Thissectiongivesan overviewfortheapplicationsofthegamma buffersand alsodefinesthegamma correction curve.Specificationsforthebuffersarederivedfromtheiroperationrange.Alsoincludedaretheformulasforthe realizationofthegamma correctioncurveusingexternalresistors.An overviewisgivenforthegamma voltage accuracy,usingtheLM8207 incombinationwithexternalresistors. As discussedinthesectionentitled“PrincipleOperationofa TFT-LCD,”thebasicfunctionofthegamma buffers istomake thegamma correctioncurveindependentofthebehaviorofthecolumn driver.Writingdatatoeach subsequentpixelwillcause loadvariations.The gamma buffershave a low impedance outputand can handle thesevariationswithoutchangingthe gamma correctioncurve.A typicalgamma correctioncurveisgivenin Figure37. Figure37. TypicalGamma CorrectionCurve Each buffercoversa partofthecorrectioncurveand,therefore,has itsown specifications.Allbuffersrequire thatthe outputshouldrecoverquicklyfrom disturbancescaused by the switchingof the column driver.The gamma voltagelevelof each buffer(VGMA1 … VGMA18) depends on itspositionforthe levelsdecrease sequentially.To bestutilizetheLM8207, each bufferisoptimizedforitspositioninthegamma correctioncurve.
- Gamma Buffers1-2 – Operatingvoltagerange:VDD toVSS +2V. Due totheoperatingvoltage,onlynegativetransitionsatthe outputare possible.Positivetransitionswillexceed the supplyvoltageVDD . These buffersare ableto sourcecurrenttobiastheresistiveloadofthecolumn driverhavingan open collectorstructure.To meet theoperatingvoltagerange,theseoutputsneed a resistiveloadconnectedtoa lowerpotentialsourcing an outputcurrentofatleast1 mA.
- Gamma Buffers3-16 – Operatingvoltagerange:VDD – 1V toVSS + 1V. Due totheoperatingrange,bothpositiveand negative transitionsattheoutputsarepossible.
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R 18 =¨ VGMA18 I and R X = ¨ VGMAx I - ¦ R y y=x+1 GAMMA_2 GAMMA_4 GAMMA_5 GAMMA_3 GAMMA_6 GAMMA_7 GAMMA_9 GAMMA_10 GAMMA_11 GAMMA_14 GAMMA_12 GAMMA_13 GAMMA_15 GAMMA_16 GAMMA_17 GAMMA_18 LM8207 14.4 V VGMA1 VGMA2 VGMA3 VGMA16 VGMA17 VGMA18 R 18 R 17 R 16 R 1 R 2 COLUMN DRIVERS GAMMA_1 GAMMA_8 LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013
- Gamma Buffers17-18 – Operatingvoltagerange:VDD - 2 to VSS . Due to the operatingvoltage,onlypositivetransitionsat the outputare possible.Negativetransitionswillexceed thenegativesupplyvoltageVSS .These buffersare ableto sinkcurrentfrom the resistiveloadof the column driverhavingan open collectorstructure.To meet the operatingvoltagerange,theseoutputsneed a resistiveloadconnectedto a higherpotential sinkingan outputcurrentofatleast1 mA Example: A typicalapplicationusing the LM8207 is given in Figure38. The correspondinggamma correctioncurve calculationsforthe resistorvaluesand forsettingthe VoltageReferenceare shown in the section“Voltage Reference.” Figure38. TypicalTFT DisplayApplicationDiagram Using theLM8207 The valuesoftheresistorsinthegamma correctioncurvearecalculatedsuch thata currentof1 mA flowsinthe resistorchain. where
- x istheindexforthecorrespondinggamma voltageand has a rangeof1 to18 (3) Using these formulasthe resistorvaluesin Table 1 are calculated.High accuracyresistorsvaluescan be realizedusing0.1% resistors.A method forfine-tuningtheresistorvalueistocombine two resistorsinseries. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 17 ProductFolderLinks:LM8207
SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com Table1.ResistorValues forDefiningtheGamma CorrectionCurve Gamma Curve Definition VGMA Node VGMA Voltage CalculatedResistance(Ω) 1 11.59 210 2 11.38 2200 3 9.18 670 4 8.51 670 5 7.84 430 6 7.41 280 7 7.13 980 8 6.15 80 9 6.07 170 10 5.90 80 11 5.82 980 12 4.84 280 13 4.56 430 14 4.13 670 15 3.46 730 16 2.73 2190 17 0.54 210 18 0.33 330 Changing the gamma correctioncurve,in combinationwiththe load of the column driverscan impact the behaviorofthegamma buffers.Gamma buffers1 and 2 are designedforoperatingvoltagesnear VDD ,and will sourcethecurrentintothecolumn drivers.Gamma buffers17 and 18 are designedforoperatingvoltagesnear VSS and willsinkthiscurrent.Buffers3 to16 are designedtooperateinthemid-voltagerange and can sinkor source current.Under specialcircumstances,by increasingthe voltagegap between gamma buffer1 and gamma buffer2, incombinationwitha low impedance loadof the column driverbetween theseoutputs,the outputofbuffer2 has tosinkmore currentthanpossible,and can saturate.Thiswillresultina settingerrorofthe inputsofthecolumn driver. For buffer17 and 18 an identicalsituationcan occur,by increasingtheoperatingvoltagerangeofbuffer17 with respecttobuffer18. A simpleand costeffectivesolutionistolowertheresistancebetween buffer2 and 3 orbuffer16 and 17,using an additionalby-passresistorR S.Thismethod ispresentedinFigure39.Thiswillnotaffectthedesiredvoltage levels,and buffer3 which has a largerlinearoutputcurrentspec willsinkthecurrentinsteadofbuffer2.The resistorvalueR S can be calculatedby thevoltagedropdividedby thecurrent.The resistorvalueshouldbe low enough tosinkthiscurrent,otherwisebuffer2 and/orbuffer17 willstillsaturate.
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OUT_1 OUT_2 OUT_3 LM8207 COLUMN DRIVER IOUT _1 IOUT _2 IOUT _3 OUT_4 IOUT _4 V4 BY-PASS RESISTOR R S LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 Figure39. Using additionalby-pass resistortoincreasecurrentsinkingcapability GAMMA VOLTAGE ACCURACY Addingbufferstothetabsofthegamma correctionresistorchainwillmake thevaluesmore independentofthe loadvariations.Unfortunately,thereare some othereffectsthatwillinfluencethegamma values.The following effectsdeterminetheaccuracyofeach gamma voltage. Majoreffectsare:
- Variationoftheinternalvoltagereference.Thiscan be foundinthe16V ElectricalCharacteristicstable.This isthemaximum variationbetween parts.
- Variationofthefeedbackresistorsused forsettingtheoutputvoltageofthevoltagereference(OUT_V REF ). Usinghighaccuracyresistorswillresultina smallvariationoftheoutputvoltagebetween differentboards
- The accuracyof the resistorsobtainedfrom the gamma correctionvoltagecurve.The gamma correction curve willbe affectedby the accuracyof the resistors.This willvary over differentboards.Temperature variationswillnotaffectthiscurve.
- Outputoffsetvoltage(VOS )ofthebuffers.VariationsofVOS (outputoffsetvoltage)ofthebuffers,willaffectthe gamma correctioncurve.The contributionofVOS ishigherforthebuffersdrivingthelowergamma voltages. Minoreffectsare:
- Inputcurrent(IBIAS)ofthegamma buffers.Variationsoftheinputcurrent(IBIAS)ofthegamma bufferscaused by temperaturechanges,willaffectthegamma correctionvoltages. VCOM BUFFER The VCOM buffersuppliesa common voltageto the back plateof allthe pixelsina TFT panel.When column driverswritetothepixels,currentpulseswilloccurontotheVCOM line.These pulsesare theresultofcharging thecapacitancebetween VCOM and thecolumn lines.Thiscapacitanceisa combinationofstraycapacitanceand pixelcapacitance.Thisstraycapacitancevariesbetween panelsizesbuttypicallyrangesfrom 16 pF to33 pF per column.Pixelcapacitanceisintheorderof0.5pF and contributesverylittletothesepulsesbecause only one pixelata timeisconnectedtoa column.Chargingthiscapacitancecan resultinshortpositiveor negative currentpulsesof100 mA or more, dependingon thepanelsize.The VCOM bufferisdesignedtohandlethese pulses.A VCOM bufferisbasicallya voltageregulatorthatcan sinkor sourcecurrentinlargecapacitiveloads. The VCOM buffershouldrecoververyfastfromthesedisturbances.The operatingvoltageoftheVCOM bufferisin themiddleofthegamma voltagerange. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 19 ProductFolderLinks:LM8207
R 2 5 k: 5 k: VCOM BUFFERLM8342 LM8207 SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com Figure40. VCOM Buffer The typicalapplicationinFigure40 shows theVCOM buffersupplyinga common voltagetotheback plateofthe display.This levelcan be adjustedby changing the value of the resistors.Increasingthe value of R 1 or decreasingthevalueofR 2 willdecreasetheVCOM level.IncreasingthevalueofR 2 ordecreasingthevalueofR 1 willincreasetheVCOM level. Another,more flexible,solutionisto use Texas Instruments’programmable VCOM calibrator,the LM8342. The VCOM levelcan be adjustedusingan I2C interface.See theLM8342 Programmable TFT V COM Calibratorwith Non-VolatileMemory datasheet(literaturenumber:snosam0 )formore detailedinformationaboutthispart. LM8207 CONFIGURATION A completeconfiguredtypicalapplicationoftheLM8207 isgiveninFigure41.Allthreebasicfunctionsofthe LM8207 are discussedin the previoussections.Detailsforsettingthe VoltageReferenceare givenin the “VoltageReference”section.Calculationsfordefininga gamma correctioncurvearegiveninthesectionentitled “Gamma Buffers.”Definingand adjustingtheVCOM levelisdiscussedinthe“VCOM Buffer”section.The LM8207 is an 18 channelgamma bufferplusa VCOM buffer.Incertainapplicationssome ofthegamma buffersortheVCOM buffermay notbe used.Insuch cases itisrecommended thattheunused bufferinputpinsbe tiedtotheinput voltagerangevalue.
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OUT_V REF IN_VREF IN_VCOM LM8207 VSS TO DISPLAY 5 k:50.6 k:14.4V VREF PROGRAMMABLE VCOM CALIBRATOR 5 k: 5 k: 2200: 670: 670: 210: 430: 280: 980: 80: 170: 80: 280: 430: 670: 730: 2190: 330: 980: 210: VDD OUT_V COM + 100 PF 10 nF ABC COLUMN DRIVERS IN_3 IN_2 IN_11 IN_12 IN_9 IN_8 IN_1 IN_10 IN_7 IN_6 IN_4 IN_5 IN_13 IN_14 IN_15 IN_16 IN_17 IN_18 OUT_1 OUT_2 OUT_4 OUT_5 OUT_3 OUT_6 OUT_7 OUT_8 OUT_9 OUT_11 OUT_14 OUT_12 OUT_13 OUT_15 OUT_16 OUT_17 OUT_18 OUT_10 16V 2800: LM8342 LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 Figure41. LM8207 Configuration Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 21 ProductFolderLinks:LM8207
SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com MAXIMUM POWER DISSIPATION The maximum power dissipationintheLM8207 TSSOP package depends on theambienttemperatureand the increaseofthejunctiontemperatureofthedie.Exceedingthemaximum temperaturewilldamage thepart.(See theAbsoluteMaximum Ratingstable.)The VCOM bufferoftheLM8207 isdesignedforuse inpulsedconditions. Drivinga continuouscurrentof severalhundred mA to a load willdamage the partdue to the high power consumptionoftheoutputstageoftheVCOM buffer. The maximum operatingtemperaturecan be calculatedusingthisformula: TJ = TA + θJA x PDISSIPATION where
- TA = Ambienttemperature
- θJA = Thermalresistanceofpackage (See OperatingRatingstable)(84°C/W)
- PDISSIPATION = Totalpower dissipationoftheLM8207 (4) Examples: The estimatedpower consumptionoftheLM8207 ina steadystatesituationwithno loadis: VDD = 16V IDD = 6 mA (allbufferswithinnormaloperatingrange) OUT_V REF = 14.4V ILOAD = 3 mA VDD x IDD = 16 V x 6 mA (VDD -OUT_V REF )x ILOAD = (16V – 14.4V) x 3 mA = 4.8mW Totalsteadystatepower dissipation = 100.8mW For an ambienttemperatureTA of40°C and a dissipatedpower of100.8mW, thejunctiontemperatureTJ willbe 49°C. Thiswillnotexceed themaximum operatingtemperature. Two issuesarenotconsideredinthecalculation:
- Continuouspower dissipationofthegamma buffers.Thisisloaddependent,and can be calculatedusingthe voltagedropovertheoutputstagetimestheoutputcurrent: – P = (VDD -VGMAx )x IOUT forcurrentsourcing – P = (VGMAx )x IOUT forcurrentsinking
- Pulsedpower dissipationofthebuffers.The RMS valueofthispulsedcurrentdepends on themagnitudeof thecurrentfluctuationsand thedutycycle.Thiscan majorlycontributetothetotalpower dissipation. When theLM8207 isinsteadystatebiasing,theV bufferisconsideredatthreevariousloadconditions: IOUTRMS (mA) VCOM Level(V) Dissipation(mW) Temp Rise TJ 10 8 80 7 56 50 8 400 35 83 100(1) 8 800 67 107 (1) When IOUTRMS = 100 mA, thepackage (TJ)willexceed theOperatingTemperature EVALUATION BOARD Fortestingpurposesan evaluationboardisavailable.Itisintendedtoevaluatethefollowingfunctions:
- The VoltageReferenceisfullyadjustablewithintheoperatingrange.For optimaloutputvoltageranges,user definedresistorscan be trimmedby usingtwo resistorsinseries.
- The Gamma correctioncurveisuserdefinedusingexternalresistors.Each optimalvaluecan be achievedby usingtwo seriesresistorsforfine-tuning.
- The VCOM node inputvoltagecan be achievedusing Texas Instruments’ LM8342 programmable VCOM calibrator,orusingan externalsupply.
- Fortesting,an additionaldummy loadcan be connectedtoalloutputsofthegamma buffers.
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R22* R23 R23* R24 R24* R28 R28* R29 R29* R30 R30* R34 R34* R35 R35* R36 R36* R39 R39* OUT_18 OUT_17 OUT_VCOM OUT_16 OUT_15 OUT_14 OUT_13 OUT_12 OUT_11 OUT_10 OUT_9 OUT_8 OUT_7 OUT_6 OUT_5 OUT_4 OUT_3 OUT_2 OUT_1 R21 R16* R16 R15* R15 R14* R14 R10* R10 R9* R8* OUT_1 OUT_2 OUT_3 OUT_4 OUT_5 OUT_6 OUT_7 OUT_8 OUT_9 OUT_10 OUT_11 OUT_12 OUT_13 OUT_14 OUT_15 OUT_16 OUT_17 OUT_18 OUT_VCOM IN_18 IN_17 IN_VCOM IN_16 IN_15 IN_14 IN_13 IN_12 IN_11 IN_10 IN_9 IN_8 IN_7 IN_6 IN_5 IN_4 IN_3 IN_2 IN_1 R17* R18 R18* R19 R19* R20 R20* R25 R25* R26 R26* R27 R27* R31 R31* R35 R32* R33 R33* R37 R37* R17 R13* R13 R12* R12 R11* R11 R6* R4* R3* R38 J5R7 R2 R2* R1 R1* 1 48 Vref 12 37 J3 J4 BANANA JACKBANANA JACK VDD VSS out _Vref in_Vref OUT_1 OUT_2 OUT_3 OUT_4 OUT_5 OUT_6 OUT_7 OUT_8 OUT_9 OUT_10 OUT_11 OUT_12 OUT_13 OUT_14 OUT_15 OUT_16 OUT_17 OUT_18 NC NC OUT_VCOM IN_1 IN_2 IN_3 IN_4 IN_5 IN_6 IN_7 IN_8 IN_9 IN_10 IN_11 IN_12 IN_13 IN_14 IN_15 IN_16 IN_17 IN_18 NC NC IN_VCOM IN_1 IN_2 IN_3 IN_4 IN_5 IN_6 IN_7 IN_8 IN_9 IN_10 IN_11 IN_12 IN_13 IN_14 IN_15 IN_16 IN_17 IN_18 IN_VCOM R21* LM8207 www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 Figure42. Schematic LM8207 EvaluationBoard Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 23 ProductFolderLinks:LM8207
SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com Figure43. Layout ofLM8207 EvaluationBoard (ActualSize)— Bottom View Figure44. Layout ofLM8207 EvaluationBoard (ActualSize)— Top View
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www.ti.com SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 LAYOUT RECOMMENDATIONS A properlayoutisnecessaryforoptimum performanceoftheLM8207. A low impedance and cleangroundplane isrecommended. The tracesfrom theVSS pintotheground planeshouldbe as shortas possible.Decoupling capacitorsshouldbe placedveryclosetotheVDD pin.Connectionsofthesedecouplingcapacitorstotheground planeshouldbe veryshort.An additionaldecouplingcapacitorforOUT_V REF isrecommended. Due totheheavy currentpeaks and shorttransitionsattheVCOM node,tracesfromtheoutputoftheVCOM buffer shouldbe low impedance and as shortas possible,tominimizebothvoltagedropsoverthetraceand unwanted EM disturbances. Copyright© 2005–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 25 ProductFolderLinks:LM8207
SNOSAL5A –SEPTEMBER 2005–REVISED MARCH 2013 www.ti.com
REVISION HISTORY
Changes from Original(March 2013)toRevisionA Page
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www.ti.com 10-Jul-2014 Addendum-Page 1 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/Ball Finish (6) MSL Peak Temp (3) Op Temp (°C) Device Marking (4/5) Samples LM8207MT/NOPB NRND TSSOP DGG 48 38 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR -40 to 105 LM8207MT LM8207MTX/NOPB NRND TSSOP DGG 48 1000 Green (RoHS & no Sb/Br) CU SN Level-2-260C-1 YEAR -40 to 105 LM8207MT (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. 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.
www.ti.com 10-Jul-2014 Addendum-Page 2 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.
*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 2-Mar-2016 Pack Materials-Page 1
*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM8207MTX/NOPB TSSOP DGG 48 1000 367.0 367.0 45.0 PACKAGE MATERIALS INFORMATION www.ti.com 2-Mar-2016 Pack Materials-Page 2
MTSS003D – JANUARY 1995 – REVISED JANUARY 1998 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 DGG (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE 4040078/F 12/97
48 PINS SHOWN
0,25 0,15 NOM Gage Plane 6,00 6,20 8,30 7,90 0,75 0,50 Seating Plane 0,27 0,17 A 1,20 MAX M0,08 0,10 0,50 0°–8° 14,10 13,90 48DIM A MAX A MIN PINS ** 12,40 12,60 17,10 16,90 0,15 0,05 NOTES: A. All linear dimensions are in millimeters. B. This drawing is subject to change without notice. C. Body dimensions do not include mold protrusion not to exceed 0,15. D. Falls within JEDEC MO-153
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