LF355

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 LF155/LF156/LF256/LF257/LF355/LF356/LF357JFETInputOperationalAmplifiers Check forSamples: LF155,LF156,LF355,LF356,LF357 1FEATURES DESCRIPTION These are thefirstmonolithicJFET inputoperational23Advantages amplifiersto incorporatewellmatched, high voltage• Replace Expensive Hybridand Module FET Op JFETs on the same chip with standard bipolarAmps transistors( BI-FET™ Technology).These amplifiers

• Rugged JFETs Allow Blow-Out Free Handling featurelow inputbiasand offsetcurrents/lowoffset voltageand offsetvoltagedrift,coupled withoffsetCompared withMOSFET InputDevices adjustwhichdoes notdegradedriftorcommon-mode• ExcellentforLow Noise ApplicationsUsing rejection.The devicesarealsodesignedforhighslewEitherHigh or Low Source Impedance — Very rate,wide bandwidth,extremelyfastsettlingtime,lowLow 1/fCorner voltageand currentnoiseand a low1/fnoisecorner.
• OffsetAdjustDoes Not Degrade Driftor Common-Mode Rejectionas inMost Common Features MonolithicAmplifiers • Low InputBiasCurrent: 30pA
• New Output Stage Allows Use ofLarge • Low InputOffsetCurrent: 3pA CapacitiveLoads (5,000pF) withoutStability • HighInputImpedance: 1012ΩProblems • Low InputNoiseCurrent: 0.01pA/√Hz
• InternalCompensation and Large Differential • HighCommon-Mode RejectionRatio: 100 dBInputVoltageCapability • LargeDC VoltageGain: 106 dB APPLICATIONS Table1.Uncommon Features
• PrecisionHigh Speed Integrators LF155/ LF156/ LF257/ Units LF355 LF256/ LF357• FastD/A and A/D Converters LF356 (AV=5)
• High Impedance Buffers Extremelyfast 4 1.5 1.5 μs settlingtimeto0.01%• Wideband, Low Noise,Low DriftAmplifiers Fastslewrate 5 12 50 V/µs• LogarithmicAmplifiers Wide gainbandwidth 2.5 5 20 MHz• PhotocellAmplifiers Low inputnoise 20 12 12 nV /√Hz• Sample and Hold Circuits voltage Pleasebe aware thatan importantnoticeconcerningavailability,standardwarranty,and use incriticalapplicationsof Texas Instrumentssemiconductorproductsand disclaimerstheretoappearsattheend ofthisdatasheet. 2BI-FETisa trademarkofTexas Instruments. 3Allothertrademarksarethepropertyoftheirrespectiveowners. PRODUCTION DATA informationiscurrentas ofpublicationdate. Copyright© 2000–2013,Texas InstrumentsIncorporatedProductsconform to specificationsper the terms of the Texas Instrumentsstandardwarranty.Productionprocessingdoes not necessarilyincludetestingofallparameters.

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com SimplifiedSchematic *3pF inLF357 series. These deviceshave limitedbuilt-inESD protection.The leadsshouldbe shortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamage totheMOS gates.

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 AbsoluteMaximum Ratings(1)(2) LF155/6 LF256/7/LF356B LF355/6/7 SupplyVoltage ±22V ±22V ±18V DifferentialInputVoltage ±40V ±40V ±30V InputVoltageRange (3) ±20V ±20V ±16V OutputShortCircuitDuration Continuous Continuous Continuous TJMAX P Package 100°C 100°C D Package 100°C 100°C Power DissipationatTA = 25°C (1)(4) P Package 670 mW 670 mW D Package 380 mW 380 mW ThermalResistance(Typical)θJA P Package 130°C/W 130°C/W D Package 195°C/W 195°C/W (Typical)θJC StorageTemperatureRange −65°C to+150°C −65°C to+150°C −65°C to+150°C SolderingInformation(LeadTemp.) Soldering(10sec.) 300°C 300°C 300°C Soldering(10sec.) 260°C 260°C 260°C Vapor Phase (60sec.) 215°C 215°C Infrared(15sec.) 220°C 220°C ESD tolerance (100pF dischargedthrough1.5kΩ) 1000V 1000V 1000V (1) The maximum power dissipationforthesedevicesmust be deratedatelevatedtemperaturesand isdictatedby TJMAX ,θJA,and the ambienttemperature,TA.The maximum availablepower dissipationatany temperatureisPD =(TJMAX −TA)/θJA orthe25°C PdMAX , whicheverisless. (2) IfMilitary/Aerospacespecifieddevicesarerequired,contacttheTISalesOffice/Distributorsforavailabilityand specifications. (3) Unlessotherwisespecifiedtheabsolutemaximum negativeinputvoltageisequaltothenegativepower supplyvoltage. (4) Max. Power Dissipationisdefinedby thepackage characteristics.OperatingthepartneartheMax. Power Dissipationmay cause the parttooperateoutsidespecifiedlimits. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com DC ElectricalCharacteristics LF256/7LF155/6 LF355/6/7LF356BSymbol Parameter Conditions Units Min Typ Max Min Typ Max Min Typ Max VOS InputOffsetVoltage R S=50Ω,TA=25°C 3 5 3 5 3 10 mV Over Temperature 7 6.5 13 mV ΔVOS /ΔT AverageTC ofInput R S=50Ω 5 5 5 μV/°COffsetVoltage ΔTC/ΔVOS Change inAverageTC R S=50Ω,(2) μV/°C0.5 0.5 0.5withVOS Adjust permV IOS InputOffsetCurrent TJ=25°C, (1)(3) 3 20 3 20 3 50 pA TJ≤THIGH 20 1 2 nA IB InputBiasCurrent TJ=25°C, (1)(3) 30 100 30 100 30 200 pA TJ≤THIGH 50 5 8 nA R IN InputResistance TJ=25°C 1012 1012 1012 Ω AVOL LargeSignalVoltage VS=±15V,TA=25°C 50 200 50 200 25 200 V/mV Gain VO =±10V,R L=2k Over Temperature 25 25 15 V/mV VO OutputVoltageSwing VS=±15V,R L=10k ±12 ±13 ±12 ±13 ±12 ±13 V VS=±15V,R L=2k ±10 ±12 ±10 ±12 ±10 ±12 V VCM InputCommon-Mode VS=±15V +15.1 ±15.1 +15.1 V ±11 ±11 +10VoltageRange −12 −12 −12 V CMRR Common-Mode 85 100 85 100 80 100 dBRejectionRatio PSRR SupplyVoltageRejection (4) 85 100 85 100 80 100 dBRatio (1) Unlessotherwisestated,thesetestconditionsapply: LF155/156 LF256/257 LF356B LF355/6/7 SupplyVoltage,VS ±15V ≤ VS ≤ ±20V ±15V ≤ VS ≤ ±20V ±15V ≤ VS ±20V VS= ±15V TA −55°C ≤ TA ≤ −25°C ≤ TA ≤ +85°C 0°C ≤ TA ≤ +70°C 0°C ≤ TA ≤ +70°C +125°C THIGH +125°C +85°C +70°C +70°C and VOS ,IB and IOS aremeasured atVCM = 0. (2) The TemperatureCoefficientoftheadjustedinputoffsetvoltagechanges onlya smallamount (0.5μV/°C typically)foreach mV of adjustmentfromitsoriginalunadjustedvalue.Common-mode rejectionand open loopvoltagegainarealsounaffectedby offset adjustment. (3) The inputbiascurrentsarejunctionleakagecurrentswhichapproximatelydoubleforevery10°C increaseinthejunctiontemperature, TJ.Due tolimitedproductiontesttime,theinputbiascurrentsmeasured arecorrelatedtojunctiontemperature.Innormaloperationthe junctiontemperaturerisesabove theambienttemperatureas a resultofinternalpower dissipation,Pd.TJ = TA + θJA Pd where θJA is thethermalresistancefromjunctiontoambient.Use ofa heatsinkisrecommended ifinputbiascurrentistobe kepttoa minimum. (4) SupplyVoltageRejectionismeasured forbothsupplymagnitudesincreasingordecreasingsimultaneously,inaccordancewithcommon practice. DC ElectricalCharacteristics TA = TJ = 25°C, VS = ±15V LF155 LF355 LF156/256/257/356B LF356 LF357 Parameter Units Typ Max Typ Max Typ Max Typ Max Typ Max Supply 2 4 2 4 5 7 5 10 5 10 mACurrent

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 AC ElectricalCharacteristics TA = TJ = 25°C, VS = ±15V LF155/355 LF156/256/ LF156/256/356/ LF257/357 356B LF356BSymbol Parameter Conditions Units Typ Min Typ Typ SR Slew Rate LF155/6:AV=1, 5 7.5 12 V/μs LF357:AV=5 50 V/μs GBW Gain BandwidthProduct 2.5 5 20 MHz ts SettlingTime to0.01% (1) 4 1.5 1.5 μs en EquivalentInputNoise R S=100Ω Voltage f=100Hz 25 15 15 nV/√Hz f=1000Hz 20 12 12 nV/√Hz in EquivalentInputCurrent f=100Hz 0.01 0.01 0.01 pA/√Hz Noise f=1000Hz 0.01 0.01 0.01 pA/√Hz C IN InputCapacitance 3 3 3 pF (1) Settlingtimeisdefinedhere,fora unitygaininverterconnectionusing2 kΩ resistorsfortheLF155/6.Itisthetimerequiredfortheerror voltage(thevoltageattheinvertinginputpinon theamplifier)tosettletowithin0.01% ofitsfinalvaluefromthetimea 10V stepinputis appliedtotheinverter.FortheLF357,AV = −5,thefeedbackresistorfromoutputtoinputis2kΩ and theoutputstepis10V (See Settling Time TestCircuit). Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com TypicalDC Performance Characteristics CurvesareforLF155 and LF156 unlessotherwisespecified. InputBias Current InputBias Current Figure1. Figure2. InputBias Current VoltageSwing Figure3. Figure4. Supply Current Supply Current Figure5. Figure6.

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 TypicalDC Performance Characteristics(continued) CurvesareforLF155 and LF156 unlessotherwisespecified. NegativeCurrentLimit PositiveCurrentLimit Figure7. Figure8. PositiveCommon-Mode NegativeCommon-Mode InputVoltageLimit InputVoltageLimit Figure9. Figure10. Open Loop VoltageGain Output VoltageSwing Figure11. Figure12. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com TypicalAC Performance Characteristics Gain Bandwidth Gain Bandwidth Figure13. Figure14. NormalizedSlew Rate Output Impedance Figure15. Figure16. Output Impedance Figure17.

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 TypicalAC Performance Characteristics(continued) LF155 Small SignalPulse Response, A V = +1 LF156 Small SignalPulse Response, A V = +1 Figure18. Figure19. LF156 Large SignalPuls LF155 Large SignalPulse Response, A V = +1 Response, A V = +1 Figure20. Figure21. InverterSettlingTime InverterSettlingTime Figure22. Figure23. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com TypicalAC Performance Characteristics(continued) Open Loop Frequency Response Bode Plot Figure24. Figure25. Bode Plot Bode Plot Figure26. Figure27. Common-Mode RejectionRatio Power Supply RejectionRatio Figure28. Figure29.

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 TypicalAC Performance Characteristics(continued) Power Supply RejectionRatio UndistortedOutput VoltageSwing Figure30. Figure31. EquivalentInputNoise EquivalentInputNoise Voltage Voltage(Expanded Scale) Figure32. Figure33. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com DETAILED SCHEMATIC *C = 3pF inLF357 series. Connection Diagrams (TopViews) *AvailableperJM38510/11401 or JM38510/11402 Figure34. TO-99 Package (LMC) Figure35. SOIC and PDIP Package (D and P) See Package Number LMC (O-MBCY-W8) See Package Number D (R-PDSO-G8) or P (R-PDIP-T8)

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 APPLICATION HINTS These areop amps withJFET inputdevices.These JFETs have largereversebreakdown voltagesfromgateto sourceand draineliminatingtheneed forclampsacrosstheinputs.Thereforelargedifferentialinputvoltagescan easilybe accommodated withouta largeincreaseininputcurrent.The maximum differentialinputvoltageis independentof the supplyvoltages.However, neitherof the inputvoltagesshouldbe allowedto exceed the negativesupplyas thiswillcause largecurrentstoflowwhichcan resultina destroyedunit. Exceeding the negativecommon-mode limiton eitherinputwillforcethe outputto a high state,potentially causinga reversalofphase totheoutput.Exceedingthenegativecommon-mode limiton bothinputswillforce the amplifieroutputto a highstate.In neithercase does a latchoccursinceraisingthe inputback withinthe common-mode rangeagainputstheinputstageand thustheamplifierina normaloperatingmode. Exceedingthepositivecommon-mode limiton a singleinputwillnotchange thephase oftheoutputhowever,if bothinputsexceed thelimit,theoutputoftheamplifierwillbe forcedtoa highstate. These amplifierswilloperatewiththe common-mode inputvoltageequal to the positivesupply.In fact,the common-mode voltagecan exceed thepositivesupplyby approximately100 mV independentofsupplyvoltage and overthefulloperatingtemperaturerange.The positivesupplycan thereforebe used as a referenceon an inputas,forexample,ina supplycurrentmonitorand/orlimiter. Precautionsshouldbe takentoensurethatthepower supplyfortheintegratedcircuitneverbecomes reversedin polarityorthattheunitisnotinadvertentlyinstalledbackwardsina socketas an unlimitedcurrentsurgethrough theresultingforwarddiodewithintheIC couldcause fusingoftheinternalconductorsand resultina destroyed unit. Allofthebiascurrentsintheseamplifiersare setby FET currentsources.The draincurrentsfortheamplifiers arethereforeessentiallyindependentofsupplyvoltage. As withmost amplifiers,careshouldbe takenwithleaddress,component placementand supplydecouplingin ordertoensurestability.For example,resistorsfromtheoutputtoan inputshouldbe placedwiththebody close totheinputtominimize“pickup”and maximizethefrequencyofthefeedbackpoleby minimizingthecapacitance fromtheinputtoground. A feedbackpoleiscreatedwhen the feedbackaround any amplifierisresistive.The parallelresistanceand capacitancefromtheinputofthedevice(usuallytheinvertinginput)toAC groundsetthefrequencyofthepole. Inmany instancesthefrequencyofthispoleismuch greaterthantheexpected3dB frequencyoftheclosedloop gainand consequentlythereisnegligibleeffecton stabilitymargin.However, ifthefeedbackpoleislessthan approximatelysixtimestheexpected3 dB frequencya leadcapacitorshouldbe placedfrom theoutputtothe inputoftheop amp. The valueoftheadded capacitorshouldbe such thattheRC timeconstantofthiscapacitor and theresistanceitparallelsisgreaterthanorequaltotheoriginalfeedbackpoletimeconstant. TypicalCircuitConnections Figure36. VOS Adjustment

• VOS isadjustedwitha 25k potentiometer
• The potentiometerwiperisconnectedtoV+
• For potentiometerswithtemperaturecoefficientof 100 ppm/°C or lessthe additionaldriftwithadjustis≈ 0.5μV/°C/mV ofadjustment
• Typicaloveralldrift:5μV/°C ±(0.5μV/°C/mV ofadj.) Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com *LF155/6R = 5k,LF357 R = 1.25k Figure37. DrivingCapacitiveLoads Due to a uniqueoutputstagedesign,theseamplifiershave the abilityto drivelargecapacitiveloadsand still maintainstability.C L(MAX) ≃ 0.01μF. Overshoot≤ 20%, Settlingtime(ts)≃ 5μs Fordistortion≤ 1% and a 20 Vp-p VOUT swing,power bandwidthis:500kHz. Figure38. LF357 -A Large Power BW Amplifier TypicalApplications Figure39. SettlingTime TestCircuit

• SettlingtimeistestedwiththeLF155/6connectedas unitygaininverterand LF357 connectedforAV = −5
• FET used toisolatetheprobecapacitance
• Output= 10V step
• AV = −5 forLF357

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 Large SignalInverterOutput,VOUT (fromSettlingTime Circuit) Figure40. LF355 Figure41. LF356 Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com Figure42. LF357 Figure43. Low DriftAdjustableVoltageReference

• Δ VOUT /ΔT = ±0.002%/°C
• Allresistorsand potentiometersshouldbe wire-wound
• P1:driftadjust
• P2:VOUT adjust
• Use LF155 for – Low IB – Low drift – Low supplycurrent

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 Figure44. FastLogarithmicConverter

• Dynamic range:100μA ≤ Ii≤ 1mA (5decades),|VO |= 1V/decade
• Transientresponse:3μs forΔIi= 1 decade
• C1, C2, R2, R3: added dynamiccompensation
• VOS adjusttheLF156 tominimizequiescenterror
• R T:TelLabs typeQ81 + 0.3%/°C Figure45. PrecisionCurrentMonitor
• VO = 5 R1/R2 (V/mA ofIS)
• R1, R2, R3: 0.1% resistors
• Use LF155 for – Common-mode rangetosupplyrange – Low IB – Low VOS – Low SupplyCurrent Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 17 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com Figure46. 8-BitD/A ConverterwithSymmetricalOffsetBinaryOperation

• R1, R2 shouldbe matched within±0.05%
• Full-scaleresponsetime:3μs EO B1 B2 B3 B4 B5 B6 B7 B8 Comments +9.920 1 1 1 1 1 1 1 1 PositiveFull-Scale +0.040 1 0 0 0 0 0 0 0 (+)Zero-Scale −0.040 0 1 1 1 1 1 1 1 (−)Zero-Scale −9.920 0 0 0 0 0 0 0 0 NegativeFull-Scale Figure47. Wide BW Low Noise,Low DriftAmplifier
• ParasiticinputcapacitanceC1 ≃ (3pF forLF155, LF156 and LF357 plusany additionallayoutcapacitance) interactswithfeedbackelementsand createsundesirablehighfrequencypole.To compensate add C2 such that:R2 C2 ≃ R1 C1. Figure48. Boosting theLF156 witha CurrentAmplifier
• IOUT(MAX) ≃150mA (willdriveR L≥ 100Ω)
• No additionalphase shiftadded by thecurrentamplifier

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 R1, R4 matched.Linearity0.1% over2 decades. Figure49. Decades VCO Figure50. IsolatingLarge CapacitiveLoads

• Overshoot6%
• ts 10μs
• When drivinglargeC L,theVOUT slewratedeterminedby C L and IOUT(MAX) : Figure51. Low DriftPeak Detector
• By addingD1 and R f,VD1 =0 duringholdmode. Leakage ofD2 providedby feedbackpaththroughR f.
• Leakage ofcircuitisessentiallyIb (LF155,LF156)pluscapacitorleakageofCp.
• DiodeD3 clampsVOUT (A1)toVIN−VD3 toimprovespeed and tolimitreversebiasofD2.
• Maximum inputfrequencyshouldbe << ½ πR fC D2 where C D2 istheshuntcapacitanceofD2. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 19 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com Figure52. Non-InvertingUnityGain OperationforLF157 Figure53. InvertingUnityGain forLF157

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 Figure54. High Impedance, Low DriftInstrumentationAmplifier

• System VOS adjustedviaA2 VOS adjust
• Trim R3 to boost up CMRR to 120 dB. Instrumentationamplifierresistorarrayrecommended forbest accuracyand lowestdrift Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 21 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

LF155,LF156,LF355,LF356,LF357 SNOSBH0C –MAY 2000–REVISED MARCH 2013 www.ti.com Figure55. FastSample and Hold

• Bothamplifiers(A1,A2) have feedbackloopsindividuallyclosedwithstableresponses(overshootnegligible)
• AcquisitiontimeTA,estimatedby:
• LF156 developsfullSr outputcapabilityforVIN ≥ 1V
• AdditionofSW2 improvesaccuracyby puttingthevoltagedropacrossSW1 insidethefeedbackloop
• Overallaccuracyofsystemdeterminedby theaccuracyofbothamplifiers,A1 and A2 Figure56. High Accuracy Sample and Hold
• By closingtheloopthroughA2,theVOUT accuracywillbe determineduniquelyby A1. – No VOS adjustrequiredforA2.
• TA can be estimatedby same considerationsas previouslybut,because oftheadded – propagationdelayinthefeedbackloop(A2)theovershootisnotnegligible.
• Overallsystemslowerthanfastsample and hold
• R1, C C :additionalcompensation
• Use LF156 for – Fastsettlingtime – Low VOS

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LF155,LF156,LF355,LF356,LF357 www.ti.com SNOSBH0C –MAY 2000–REVISED MARCH 2013 Figure57. High Q Band Pass Filter

• By addingpositivefeedback(R2)
• Q increasesto40
• fBP = 100 kHz
• Cleanlayoutrecommended
• Response toa 1Vp-p toneburst:300μs Figure58. High Q Notch Filter
• 2R1 = R = 10M Ω – 2C = C1 = 300pF
• Capacitorsshouldbe matched toobtainhighQ
• fNOTCH = 120 Hz, notch= −55 dB, Q > 100
• Use LF155 for – Low IB – Low supplycurrent Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 23 ProductFolderLinks:LF155 LF156 LF355 LF356 LF357

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REVISION HISTORY

Changes from RevisionB (March 2013)toRevisionC Page

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www.ti.com 1-Nov-2013 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 LF156H ACTIVE TO-99 LMC 8 500 TBD Call TI Call TI -55 to 125 LF156H LF156H/NOPB ACTIVE TO-99 LMC 8 500 Green (RoHS & no Sb/Br) POST-PLATE Level-1-NA-UNLIM -55 to 125 LF156H LF256H ACTIVE TO-99 LMC 8 500 TBD Call TI Call TI -25 to 85 LF256H LF256H/NOPB ACTIVE TO-99 LMC 8 500 Green (RoHS & no Sb/Br) POST-PLATE Level-1-NA-UNLIM -25 to 85 LF256H LF356H ACTIVE TO-99 LMC 8 500 TBD Call TI Call TI 0 to 70 LF356H LF356H/NOPB ACTIVE TO-99 LMC 8 500 Green (RoHS & no Sb/Br) POST-PLATE Level-1-NA-UNLIM 0 to 70 LF356H LF356M NRND SOIC D 8 95 TBD Call TI Call TI 0 to 70 LF356 M LF356M/NOPB ACTIVE SOIC D 8 95 Green (RoHS & no Sb/Br) SN | CU SN Level-1-260C-UNLIM 0 to 70 LF356 M LF356MX NRND SOIC D 8 2500 TBD Call TI Call TI 0 to 70 LF356 M LF356MX/NOPB ACTIVE SOIC D 8 2500 Green (RoHS & no Sb/Br) SN | CU SN Level-1-260C-UNLIM 0 to 70 LF356 M LF356N NRND PDIP P 8 40 TBD Call TI Call TI 0 to 70 LF 356N LF356N/NOPB ACTIVE PDIP P 8 40 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM 0 to 70 LF 356N (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.

www.ti.com 1-Nov-2013 Addendum-Page 2 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. 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 11-Oct-2013 Pack Materials-Page 1

*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LF356MX SOIC D 8 2500 367.0 367.0 35.0 LF356MX/NOPB SOIC D 8 2500 367.0 367.0 35.0 PACKAGE MATERIALS INFORMATION www.ti.com 11-Oct-2013 Pack Materials-Page 2

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