LM1815 Adaptive Variable Reluctance Sensor Amplifier datasheet (Rev. F)
Document overview
- Manufacturer or author: Texas Instruments, Incorporated [SNOSBU8,F]
- PDF pages: 18
Technical content
www.ti.com SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 LM1815AdaptiveVariableReluctanceSensorAmplifier Check forSamples: LM1815 1FEATURES DESCRIPTION The LM1815 is an adaptivesense amplifierand 2• AdaptiveHysteresis defaultgatingcircuitformotor controlapplications.• SingleSupply Operation The sense amplifierprovidesa one-shotpulseoutput
- Ground Referenced Input whose leadingedge coincideswith the negative- going zero crossingof a ground referencedinput• True Zero Crossing Timing Reference signalsuch as from a variablereluctancemagnetic• Operates from 2V to12V Supply Voltage pick-upcoil.
- Handles Inputsfrom 100 mV P-P toover 120VP-P In normal operation,thistimingreferencesignaliswithExternalResistor processed (delayed)externallyand returnedto the• CMOS Compatible Logic LM1815. A Logicinputisthen able to selecteither the timingreferenceor the processed signalfor APPLICATIONS transmissiontotheoutputdriverstage.
- PositionSensing withNotched Wheels The adaptivesense amplifieroperateswitha positive- going thresholdwhich isderivedby peak detecting• Zero Crossing Switch theincomingsignaland dividingthisdown. Thus the• Motor Speed Control inputhysteresisvarieswithinputsignalamplitude.• Tachometer Thisenablesthe circuitto sense insituationswhere
- Engine Testing the highspeed noiseisgreaterthan the low speed signalamplitude.Minimum inputsignalis150mV P-P. Connection Diagram Figure1. Top View 14-Lead SOIC or PDIP See D or NFF0014A Package These deviceshave limitedbuilt-inESD protection.The leadsshouldbe shortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamage totheMOS gates. Pleasebe aware thatan importantnoticeconcerningavailability,standardwarranty,and use incriticalapplicationsof Texas Instrumentssemiconductorproductsand disclaimerstheretoappearsattheend ofthisdatasheet. 2Alltrademarksarethepropertyoftheirrespectiveowners. PRODUCTION DATA informationiscurrentas ofpublicationdate. Copyright© 2000–2013,Texas InstrumentsIncorporatedProductsconform to specificationsper the terms of the Texas Instrumentsstandardwarranty.Productionprocessingdoes not necessarilyincludetestingofallparameters.
SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 www.ti.com AbsoluteMaximum Ratings(1)(2) SupplyVoltage 12V Power Dissipation(3) 1250 mW OperatingTemperatureRange −40°C ≤ TA ≤ +125°C StorageTemperatureRange −65°C ≤ TJ ≤ +150°C JunctionTemperature +150°C InputCurrent ±30 mA Lead Temperature(Soldering,10 sec.) 260°C (1) “AbsoluteMaximum Ratings”arethosevaluesbeyond whichthesafetyofthedevicecannotbe ensured.They arenotmeant toimply thatthedevicesshouldbe operatedattheselimits.The tableof“ElectricalCharacteristics”specifiesconditionsofdeviceoperation. (2) IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheTexas InstrumentsSalesOffice/Distributorsforavailabilityand specifications. (3) Foroperationatelevatedtemperatures,thedevicemust be deratedbased on a 150°C maximum junctiontemperatureand a thermal resistanceof80°C/W (DIP),120°C/W (SO-14)junctiontoambient. ElectricalCharacteristics (TA = 25°C, VCC = 10V,unlessotherwisespecified,see Figure17) Parameter Conditions Min Typ Max Units OperatingSupplyVoltage 2.5 10 12 V SupplyCurrent Pin3 = -0.1V,Pin9 = 2V,Pin11 = 0.8V 3.6 6 mA ReferencePulseWidth fIN = 1Hz to2kHz,R = 150kΩ,C = 0.001µF 70 100 130 µs LogicInputBiasCurrent VIN = 2V,(Pin9 and Pin11) 5 µA SignalInputBiasCurrent VIN = 0V dc,(Pin3) -200 nA LogicThreshold (Pin9 and Pin11) 0.8 1.1 2.0 V VOUT High R L = 1kΩ,(Pin10) 7.5 8.6 V VOUT Low ISINK = 0.1mA,(Pin10) 0.3 0.4 V OutputLeakage Pin12 V12 = 11V 0.01 10 µA SaturationVoltageP12 I12 = 2mA 0.2 0.4 V InputZeroCrossingThreshold AllModes, VSIGNAL = 1V pk-pk -25 0 25 mV (1) Mode 1,Pin5 = Open 30 45 60 mV (1) Minimum InputArmingThreshold Mode 2,Pin5 = VCC 200 300 450 mV (1) Mode 3,Pin5 = Gnd -25 0 25 mV (1) Mode 1,Pin5 = Open 40 80 90 % (1) VSIGNAL ≥ 230mV pk-pk(2) Mode 2,Pin5 = VCCAdaptiveInputArmingThreshold 80 % (1) VSIGNAL ≥ 1.0Vpk-pk(2) Mode 3,Pin5 = Gnd 80 % (1) VSIGNAL ≥ 150mV pk-pk(2) (1) The Min/TypMax limitsarerelativetothepositivevoltagepeak seen atVIN Pin3. (2) TestedperFigure17,VSIGNAL isa SineWave; FSIGNAL is1000Hz.
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www.ti.com SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 TypicalPerformance Characteristics Mode 1 Minimum Arming Threshold Mode 2 Minimum Arming Threshold vs Temperature vs Temperature Figure2. Figure3. Mode 3 Minimum Arming Threshold vs Temperature Mode 1 Minimum Arming Thresholdvs VCC Figure4. Figure5. Mode 2 Minimum Arming Thresholdvs VCC Pin 3 VIN vs VSIGNAL Figure6. Figure7. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:LM1815
SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 www.ti.com TypicalPerformance Characteristics(continued) Pin 3 VIN vs VSIGNAL ,R IN = 10kΩ Pin 3 VIN vs VSIGNAL ,R IN = 20kΩ Figure8. Figure9. Pin 3 VIN vs VSIGNAL ,R IN = 50kΩ Pin 3 Bias Currentvs Temperature Figure10. Figure11. Peak DetectorCharge Current vs Temperature Peak DetectorCharge Currentvs VCC Figure12. Figure13.
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www.ti.com SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 TypicalPerformance Characteristics(continued) Peak DetectorVoltage Peak DetectorVoltage vs Pin 3 VIN,Mode 1 vs Pin 3 VIN,Mode 2 Figure14. Figure15. Peak DetectorVoltage vs Pin 3 VIN,Mode 3 Figure16. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:LM1815
SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 www.ti.com TRUTH TABLE SignalInput RC Timing InputSelect Timing Input Gated Output Pin 3 Pin 14 Pin 11 Pin 9 Pin 10 ± Pulses RC L X Pulses= RC X X H H H X X H L L ± Pulses L L L ZeroCrossing Figure17. LM1815 AdaptiveSense Amplifier
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www.ti.com SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 Schematic Diagram Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:LM1815
SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 www.ti.com APPLICATION HINTS Figure18. LM1815 Oscillograms INPUT VOLTAGE CLAMP The signalinputvoltageatpin3 isinternallyclamped.CurrentlimitfortheInputpinisprovidedby an external resistorwhich shouldbe selectedto allowa peak currentof ±3 mA innormal operation.Positiveinputsare clamped by a 1kΩ resistorand seriesdiode(seeR4 and Q12 intheinternalschematicdiagram),whilean active clamp limitspin3 totypically350mV below Ground fornegativeinputs(seeR2, R3, Q10, and Q11 intheinternal schematicdiagram).Thus forinputsignaltransitionsthatare more than 350mV below Ground, the inputpin current(up to 3mA) willbe pulledfrom the V+ supply.Ifthe V+ pinisnot adequatelybypassed the resulting voltagerippleat the V+ pinwilldisruptnormal deviceoperation.Likewise,forinputsignaltransitionsthatare more than500mV above Ground,theinputpincurrentwillbe dumped toGround throughdevicepin2.Slight shiftsin the Ground potentialat devicepin 2, due to poor groundingtechniquesrelativeto the inputsignal ground,can cause unreliableoperation.As always,adequatedevicegrounding,and V+ bypassing,needs tobe consideredacrosstheentireinputvoltageand frequencyrangefortheintendedapplication. INPUT CURRENT LIMITING As statedearlier,currentlimitingfortheInputpinisprovidedby a usersuppliedexternalresistor.Forpurposesof selectingthe appropriateresistorvaluethe Inputpin shouldbe consideredto be a zero ohm connectionto ground.For applicationswhere theinputvoltagesignalisnotsymmetricalwithrelationshiptoGround theworst case voltagepeak shouldbe used. Minimum Rext= [(Vinpeak)/3mA] Intheapplicationexample shown inFigure17 (Rext= 18kΩ)therecommended maximum inputsignalvoltageis ±54V (i.e.108Vp-p). OPERATION OF ZERO CROSSING DETECTOR The LM1815 isdesignedtooperateas a zerocrossingdetector,triggeringan internalone shoton thenegative- goingedge oftheinputsignal.Unlikeotherzerocrossingdetectors,theLM1815 cannotbe triggereduntilthe inputsignalhas crossedan "arming"thresholdon thepositive-goingportionofthewaveform.The armingcircuit isresetwhen the chipistriggered,and subsequentzero crossingsare ignoreduntilthe arming thresholdis exceeded again.Thisthresholdvariesdependingon theconnectionatpin5.Three differentmodes ofoperation arepossible:
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www.ti.com SNOSBU8F –SEPTEMBER 2000–REVISED MARCH 2013 MODE 1,PIN 5 OPEN The adaptivemode isselectedby leavingdevicepin5 open circuit.For inputsignalsoflessthan±135mV (i.e. 270 mVp-p) and greaterthantypically±75mV (i.e.150mVp-p),theinputarmingthresholdistypicallyat45mV. Under theseconditionstheinputsignalmust firstcrossthe45mV thresholdinthepositivedirectiontoarm the zerocrossingdetector,and thencrosszerointhenegativedirectiontotriggerit. Ifthesignalislessthan30mV peak (minimum ratinginElectricalCharacteristics),theone shotisensuredtonot trigger. Inputsignalsof greaterthan±230mV (i.e.460 mVp-p) willcause the arming thresholdto trackat 80% of the peak inputvoltage.A peak detectorcapacitoratdevicepin7 storesa valuerelativetothepositiveinputpeaks to establishthearmingthreshold.Inputsignalsmust exceed thisthresholdinthepositivedirectiontoarm thezero crossingdetector,whichcan thenbe triggeredby a negative-goingzerocrossing. The peak detectortracksrapidlyas the inputsignalamplitudeincreases,and decays by virtueof the resistor connectedexternallyatpin7 trackdecreasesintheinputsignal. Iftheinputsignalamplitudefallsfasterthanthevoltagestoredon thepeak detectorcapacitortheremay be a lossofoutputsignaluntilthecapacitorvoltagehas decayed toan appropriatelevel. Note thatsincetheinputvoltageisclamped,thewaveform observedatpin3 isnotidenticaltothewaveform observedat the variablereluctancesensor.Similarly,the voltagestoredat pin7 isnot identicalto the peak voltageappearingatpin3. MODE 2,PIN 5 CONNECTED TO V+ The inputarmingthresholdisfixedat200mV minimum when devicepin5 isconnectedtothepositivesupply. The chiphas no outputforsignalsoflessthan±200 mV (i.e.400mVp-p) and triggerson thenextnegative-going zerocrossingwhen thearmingthresholdishas been exceeded. MODE 3,PIN 5 GROUNDED With pin5 grounded,theinputarmingthresholdissetto0V, ±25mV maximum. Positive-goingzerocrossings arm thechip,and thenextnegative-goingzerocrossingtriggersit.Thisistheverybasicform ofzero-crossing detection. ONE SHOT TIMING The one shottimingissetby a resistorand capacitorconnectedtopin14.The recommended maximum resistor valueis150kohms. The capacitorvaluecan be changed as needed, as longas the capacitortypedoes not presentany signfigantleakagethatwouldadverselyaffecttheRC timeconstant. The outputpulsewidthis: pulsewidth= 0.673x R x C (1) Fora givenOne Shotpulsewidth,therecommended maximum inputsignalfrequencyis: Fin(max)= 1/(1.346x R x C) (2) In the applicationexample shown inFigure17 (R=150kohms, C=0.001µF) the recommended maximum input frequencywilltypicallybe 5kHz.Operatingwithinputfrequenciesabove therecommended Fin(max)valuemay resultinunreliableperformanceoftheOne Shot circuitry.For thoseapplicationswhere theOne Shot circuitis notrequired,devicepin14 can be tieddirectlytoGround. LOGIC INPUTS Insome systemsitisnecessarytoexternallygeneratepulses,such as duringstallconditionswhen thevariable reluctancesensorhas no output.Externalpulseinputsatpin9 are gatedthroughtopin10 when InputSelect (pin11)ispulledhigh.Pin12 isa directoutputfortheone shotand isunaffectedby thestatusofpin11. Input/outputpins9, 11, 10, and 12 are allCMOS logiccompatible.In addition,pins9, 11, and 12 are TTL compatible.Pin10 isnotensuredtodrivea TTL load. Pins1,4,6 and 13 have no internalconnectionsand can be grounded. Copyright© 2000–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:LM1815
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REVISION HISTORY
Changes from RevisionE (March 2013)toRevisionF Page
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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) LM1815M/NOPB Obsolete Production SOIC (D) | 14 - - Call TI Call TI -40 to 125 LM1815M LM1815MX/NOPB Active Production SOIC (D) | 14 2500 | LARGE T&R Yes SN Level-1-260C-UNLIM -40 to 125 LM1815M LM1815MX/NOPB.B Active Production SOIC (D) | 14 2500 | LARGE T&R Yes SN Level-1-260C-UNLIM -40 to 125 LM1815M LM1815N/NOPB Obsolete Production PDIP (NFF) | 14 - - Call TI Call TI - LM1815N (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
PACKAGE MATERIALS INFORMATION www.ti.com 31-Oct-2024 TAPE AND REEL INFORMATION Reel Width (W1) REEL DIMENSIONS A0B0K0WDimension designed to accommodate the component lengthDimension designed to accommodate the component thicknessOverall width of the carrier tapePitch between successive cavity centersDimension designed to accommodate the component width TAPE DIMENSIONSK0 P1B0WA0Cavity QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE Pocket QuadrantsSprocket HolesQ1Q1Q2Q2Q3Q3Q4Q4User Direction of Feed P1ReelDiameter *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 Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION www.ti.com 31-Oct-2024 TAPE AND REEL BOX DIMENSIONS Width (mm) W LH *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM1815MX/NOPB SOIC D 14 2500 367.0 367.0 35.0 Pack Materials-Page 2
www.ti.com PACKAGE OUTLINE C TYP6.2 5.8
1.75 MAX
12X 1.27 14X 0.51 0.31 7.62 TYP0.25 0.13 0 - 8 0.25 0.10 0.25 GAGE PLANE 1.27 0.40 A NOTE 3 8.75 8.55 B NOTE 4 4.0 3.8 4220718/A 09/2016 SOIC - 1.75 mm max heightD0014A SMALL OUTLINE INTEGRATED CIRCUIT NOTES: 1. All linear dimensions are in millimeters. Dimensions in parenthesis are for reference only. Dimensioning and tolerancing per ASME Y14.5M. 2. This drawing is subject to change without notice. 3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not exceed 0.15 mm, per side. 4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.43 mm, per side. 5. Reference JEDEC registration MS-012, variation AB. 1 14
0.25 C A B
0.1 C SEE DETAIL A DETAIL A TYPICAL SCALE 1.800
www.ti.com EXAMPLE BOARD LAYOUT (5.4)
0.07 MAX
0.07 MIN
14X (1.55) 14X (0.6) 12X (1.27) (R0.05) TYP 4220718/A 09/2016 SOIC - 1.75 mm max heightD0014A SMALL OUTLINE INTEGRATED CIRCUIT SYMM SYMM LAND PATTERN EXAMPLE SCALE:8X 7 8 NOTES: (continued) 6. Publication IPC-7351 may have alternate designs. 7. Solder mask tolerances between and around signal pads can vary based on board fabrication site. METALSOLDER MASK OPENING NON SOLDER MASK DEFINED SOLDER MASK DETAILS SOLDER MASK OPENING METAL UNDER SOLDER MASK SOLDER MASK DEFINED
www.ti.com EXAMPLE STENCIL DESIGN (5.4) 12X (1.27) 14X (0.6) 14X (1.55) 4220718/A 09/2016 SOIC - 1.75 mm max heightD0014A SMALL OUTLINE INTEGRATED CIRCUIT NOTES: (continued) 8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate design recommendations. 9. Board assembly site may have different recommendations for stencil design. SYMM SYMM 7 8 SOLDER PASTE EXAMPLE BASED ON 0.125 mm THICK STENCIL SCALE:8X
www.ti.com N14A (Rev G)
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