LM828 www.ti.com SNOS035D–MARCH2010–REVISEDMAY2013 LM828 Switched Capacitor Voltage Converter CheckforSamples:LM828 FEATURES DESCRIPTION 1 • InvertsInputSupplyVoltage The LM828 CMOS charge-pump voltage converter 2 inverts a positive voltage in the range of +1.8V to • SOT-23Package +5.5V to the corresponding negative voltage of −1.8V • 20ΩTypicalOutputImpedance to −5.5V. The LM828 uses two low cost capacitors to • 97%TypicalConversionEfficiencyat5mA provideupto25mAofoutputcurrent. The LM828 operates at 12 kHz switching frequency APPLICATIONS to reduce output resistance and voltage ripple. With an operating current of only 40 µA (operating • CellularPhones efficiency greater than 96% with most loads), the • Pagers LM828 provides ideal performance for battery • PDAs powered systems. The device is in a tiny SOT-23 • OperationalAmplifierPowerSupplies package. • InterfacePowerSupplies • HandheldInstruments Basic Application Circuits VoltageInverter +5Vto−10VConverter 1 Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsof TexasInstrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet. Alltrademarksarethepropertyoftheirrespectiveowners. 2 PRODUCTIONDATAinformationiscurrentasofpublicationdate. Copyright©2010–2013,TexasInstrumentsIncorporated Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarilyincludetestingofallparameters.

LM828 SNOS035D–MARCH2010–REVISEDMAY2013 www.ti.com Thesedeviceshavelimitedbuilt-inESDprotection.Theleadsshouldbeshortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamagetotheMOSgates. Absolute Maximum Ratings(1)(2) SupplyVoltage(V+toGND,orGNDtoOUT) 5.8V V+andOUTContinuousOutputCurrent 50mA OutputShort-CircuitDurationtoGND(3) 1sec. ContinuousPowerDissipation(T =25°C)(4) 240mW A T (4) 150°C JMax θ (4) 300°C/W JA OperatingJunctionTemperatureRange −40°Cto85°C StorageTemperatureRange −65°Cto+150°C LeadTemp.(Soldering,10seconds) 300°C ESDRating(5) 2kV (1) Absolutemaximumratingsindicatelimitsbeyondwhichdamagetothedevicemayoccur.Electricalspecificationsdonotapplywhen operatingthedevicebeyonditsratedoperatingconditions. (2) IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheTexasInstrumentsSalesOffice/Distributorsforavailabilityand specifications. (3) OUTmaybeshortedtoGNDforonesecondwithoutdamage.However,shortingOUTtoV+maydamagethedeviceandshouldbe avoided.Also,fortemperaturesabove85°C,OUTmustnotbeshortedtoGNDorV+,orthedevicemaybedamaged. (4) ThemaximumallowablepowerdissipationiscalculatedbyusingP =(T −T )/θ ,whereT isthemaximumjunction DMax JMax A JA JMax temperature,T istheambienttemperature,andθ isthejunction-to-ambientthermalresistanceofthepackage. A JA (5) Thehumanbodymodelisa100pFcapacitordischargedthrougha1.5kΩresistorintoeachpin. Electrical Characteristics LimitsinstandardtypefaceareforT =25°C,andlimitsinboldfacetypeapplyoverthefulloperatingtemperaturerange. J Unlessotherwisespecified:V+=5V,C =C =10μF.(1) 1 2 Symbol Parameter Condition Min Typ Max Units V+ SupplyVoltage R =10kΩ 1.8 5.5 V L I SupplyCurrent NoLoad 40 75 µA Q 115 R OutputResistance(2) I =5mA 20 65 Ω OUT L f OscillatorFrequency(3) Internal 12 24 56 kHz OSC f SwitchingFrequency(3) MeasuredatCAP+ 6 12 28 kHz SW P PowerEfficiency I =5mA 97 % EFF L V VoltageConversionEfficiency NoLoad 95 99.96 % OEFF (1) Inthetestcircuit,capacitorsC andC are10µF,0.3ΩmaximumESRcapacitors.CapacitorswithhigherESRwillincreaseoutput 1 2 resistance,reduceoutputvoltageandefficiency. (2) SpecifiedoutputresistanceincludesinternalswitchresistanceandcapacitorESR.Seethedetailsintheapplicationinformation. (3) Theoutputswitchesoperateatonehalfoftheoscillatorfrequency,f =2f . OSC SW 2 SubmitDocumentationFeedback Copyright©2010–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM828

LM828 www.ti.com SNOS035D–MARCH2010–REVISEDMAY2013 Test Circuit *C andC are10µFcapacitors. 1 2 Figure1. LM828TestCircuit Typical Performance Characteristics (CircuitofFigure1,V+=5Vunlessotherwisespecified) SupplyCurrentvs SupplyCurrentvs SupplyVoltage Temperature Figure2. Figure3. OutputSourceResistance OutputSourceResistance vs vs SupplyVoltage Temperature Figure4. Figure5. Copyright©2010–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:LM828

LM828 SNOS035D–MARCH2010–REVISEDMAY2013 www.ti.com Typical Performance Characteristics (continued) (CircuitofFigure1,V+=5Vunlessotherwisespecified) OutputVoltage Efficiencyvs vsLoadCurrent LoadCurrent Figure6. Figure7. SwitchingFrequencyvs SwitchingFrequencyvs SupplyVoltage Temperature Figure8. Figure9. CONNECTION DIAGRAMS 5-Lead SOT-23 Package (DBV) Figure10.SOT-23Package– TopView Figure11.ActualSize SeePackageNumberDBV0005A 4 SubmitDocumentationFeedback Copyright©2010–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM828

LM828 www.ti.com SNOS035D–MARCH2010–REVISEDMAY2013 Pin Functions PINDESCRIPTIONS Pin Name Function 1 OUT Negativevoltageoutput. 2 V+ Powersupplypositiveinput. 3 CAP− Connectthispintothenegativeterminalofthecharge-pumpcapacitor. 4 GND Powersupplygroundinput. 5 CAP+ Connectthispintothepositiveterminalofthecharge-pumpcapacitor. Circuit Description The LM828 contains four large CMOS switches which are switched in a sequence to invert the input supply voltage. Energy transfer and storage are provided by external capacitors. Figure 12 illustrates the voltage conversion scheme. When S and S are closed, C charges to the supply voltage V+. During this time interval, 1 3 1 switches S and S are open. In the second time interval, S and S are open; at the same time, S and S are 2 4 1 3 2 4 closed,C ischargingC .Afteranumberofcycles,thevoltageacrossC willbepumpedtoV+.Sincetheanode 1 2 2 of C is connected to ground, the output at the cathode of C equals −(V+) when there is no load current. The 2 2 output voltage drop when a load is added is determined by the parasitic resistance (R of the MOSFET ds(on) switchesandtheESRofthecapacitors)andthechargetransferlossbetweencapacitors. Figure12. VoltageInvertingPrinciple Application Information SIMPLENEGATIVEVOLTAGECONVERTER The main application of LM828 is to generate a negative supply voltage. The voltage inverter circuit uses only two external capacitors as shown in the Basic Application Circuits. The range of the input supply voltage is 1.8V to5.5V. The output characteristics of this circuit can be approximated by an ideal voltage source in series with a resistance. The voltage source equals −(V+). The output resistance, R , is a function of the ON resistance of out the internal MOSFET switches, the oscillator frequency, the capacitance and the ESR of both C and C . Since 1 2 the switching current charging and discharging C is approximately twice as the output current, the effect of the 1 ESR of the pumping capacitor C will be multiplied by four in the output resistance. The output capacitor C is 1 2 charging and discharging at a current approximately equal to the output current, therefore, this ESR term only countsonceintheoutputresistance.AgoodapproximationofR is: out (1) whereR isthesumoftheONresistanceoftheinternalMOSFETswitchesshowninFigure12. SW Highcapacitance,lowESRcapacitorswillreducetheoutputresistance. Thepeak-to-peakoutputvoltagerippleisdeterminedbytheoscillatorfrequency,thecapacitanceandESRofthe outputcapacitorC : 2 Copyright©2010–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:LM828

LM828 SNOS035D–MARCH2010–REVISEDMAY2013 www.ti.com (2) Again,usingalowESRcapacitorwillresultinlowerripple. CAPACITORSELECTION The output resistance and ripple voltage are dependent on the capacitance and ESR values of the external capacitors.Theoutputvoltagedropistheloadcurrenttimestheoutputresistance,andthepowerefficiencyis (3) Where I (V+) is the quiescent power loss of the IC device, and I 2R is the conversion loss associated with the Q L out switchon-resistance,thetwoexternalcapacitorsandtheirESRs. The selection of capacitors is based on the specifications of the dropout voltage (which equals I R ), the out out output voltage ripple, and the converter efficiency. Low ESR capacitors (following table) are recommended to maximizeefficiency,reducetheoutputvoltagedropandvoltageripple. LowESRCapacitorManufacturers Manufacturer Phone CapacitorType NichiconCorp. (708)-843-7500 PL&PFseries,through-holealuminumelectrolytic AVXCorp. (803)-448-9411 TPSseries,surface-mounttantalum Sprague (207)-324-4140 593D,594D,595Dseries,surface-mounttantalum Sanyo (619)-661-6835 OS-CONseries,through-holealuminumelectrolytic Murata (800)-831-9172 Ceramicchipcapacitors TaiyoYuden (800)-348-2496 Ceramicchipcapacitors Tokin (408)-432-8020 Ceramicchipcapacitors OtherApplications PARALLELINGDEVICES Any number of LM828s can be paralleled to reduce the output resistance. Each device must have its own pumping capacitor C , while only one output capacitor C is needed as shown in Figure 13. The composite 1 out outputresistanceis: (4) Figure13. LoweringOutputResistancebyParallelingDevices 6 SubmitDocumentationFeedback Copyright©2010–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM828

LM828 www.ti.com SNOS035D–MARCH2010–REVISEDMAY2013 CASCADINGDEVICES Cascading the LM828s is an easy way to produce a greater negative voltage (e.g. A two-stage cascade circuit is showninFigure14). If n is the integer representing the number of devices cascaded, the unloaded output voltage V is (-nV ). The out in effectiveoutputresistanceisequaltotheweightedsumofeachindividualdevice: R =nR +n/2R +...+R (5) out out_1 out_2 out_n This can be seen by first assuming that each device is 100 percent efficient. Since the output voltage is different on each device the output current is as well. Each cascaded device sees less current at the output than the previous so the R voltage drop is lower in each device added. Note that, the number of n is practically limited OUT since the increasing of n significantly reduces the efficiency, and increases the output resistance and output voltageripple. Figure14. IncreasingOutputVoltagebyCascadingDevices COMBINEDDOUBLERANDINVERTER In Figure 15, the LM828 is used to provide a positive voltage doubler and a negative voltage converter. Note that thetotalcurrentdrawnfromthetwooutputsshouldnotexceed40mA. Figure15. CombinedVoltageDoublerandInverter Copyright©2010–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:LM828

LM828 SNOS035D–MARCH2010–REVISEDMAY2013 www.ti.com REGULATINGV OUT It is possible to regulate the negative output of the LM828 by use of a low dropout regulator (such as the LP2980). The whole converter is depicted in Figure 16. This converter can give a regulated output from −1.8V to −5.5Vbychoosingtheproperresistorratio: V =V (1+R /R ) (6) out ref 1 2 where,V =1.23V (7) ref Notethatthefollowingconditionsmustbesatisfiedsimultaneouslyforworstcasedesign: V >V +V (LP2980) (8) in_min out_min drop_max +I ×R (LM828) (9) out_max out_max V <V +V (LP2980) (10) in_max out_max drop_min +I ×R (LM828) (11) out_min out_min Figure16. CombiningLM828withLP2980toMakeaNegativeAdjustableRegulator 8 SubmitDocumentationFeedback Copyright©2010–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM828

LM828 www.ti.com SNOS035D–MARCH2010–REVISEDMAY2013 REVISION HISTORY ChangesfromRevisionC(May2013)toRevisionD Page • ChangedlayoutofNationalDataSheettoTIformat............................................................................................................ 8 Copyright©2010–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:LM828

PACKAGE OPTION ADDENDUM www.ti.com 6-Feb-2020 PACKAGING INFORMATION Orderable Device Status Package Type Package Pins Package Eco Plan Lead/Ball Finish MSL Peak Temp Op Temp (°C) Device Marking Samples (1) Drawing Qty (2) (6) (3) (4/5) LM828M5 NRND SOT-23 DBV 5 1000 TBD Call TI Call TI S08A LM828M5/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS SN Level-1-260C-UNLIM -40 to 85 S08A & no Sb/Br) LM828M5X NRND SOT-23 DBV 5 3000 TBD Call TI Call TI S08A LM828M5X/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS SN Level-1-260C-UNLIM -40 to 85 S08A & no Sb/Br) (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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based flame retardants must also meet the <=1000ppm threshold requirement. (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. Addendum-Page 1

PACKAGE OPTION ADDENDUM www.ti.com 6-Feb-2020 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 2

PACKAGE MATERIALS INFORMATION www.ti.com 29-Sep-2019 TAPE AND REEL INFORMATION *Alldimensionsarenominal Device Package Package Pins SPQ Reel Reel A0 B0 K0 P1 W Pin1 Type Drawing Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant (mm) W1(mm) LM828M5 SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q2 LM828M5/NOPB SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q2 LM828M5X SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q2 LM828M5X/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q2 PackMaterials-Page1

PACKAGE MATERIALS INFORMATION www.ti.com 29-Sep-2019 *Alldimensionsarenominal Device PackageType PackageDrawing Pins SPQ Length(mm) Width(mm) Height(mm) LM828M5 SOT-23 DBV 5 1000 210.0 185.0 35.0 LM828M5/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM828M5X SOT-23 DBV 5 3000 210.0 185.0 35.0 LM828M5X/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0 PackMaterials-Page2

PACKAGE OUTLINE DBV0005A SOT-23 - 1.45 mm max height SCALE 4.000 SMALL OUTLINE TRANSISTOR C 3.0 2.6 0.1 C 1.75 1.45 1.45 B A 0.90 PIN 1 INDEX AREA 1 5 2X 0.95 3.05 2.75 1.9 1.9 2 4 3 0.5 5X 0.3 0.15 0.2 C A B (1.1) TYP 0.00 0.25 GAGE PLANE 0.22 TYP 0.08 8 TYP 0.6 0 0.3 TYP SEATING PLANE 4214839/E 09/2019 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. Refernce JEDEC MO-178. 4. Body dimensions do not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not exceed 0.15 mm per side. www.ti.com

EXAMPLE BOARD LAYOUT DBV0005A SOT-23 - 1.45 mm max height SMALL OUTLINE TRANSISTOR PKG 5X (1.1) 1 5 5X (0.6) SYMM (1.9) 2 2X (0.95) 3 4 (R0.05) TYP (2.6) LAND PATTERN EXAMPLE EXPOSED METAL SHOWN SCALE:15X SOLDER MASK SOLDER MASK METAL UNDER METAL OPENING OPENING SOLDER MASK EXPOSED METAL EXPOSED METAL 0.07 MAX 0.07 MIN ARROUND ARROUND NON SOLDER MASK SOLDER MASK DEFINED DEFINED (PREFERRED) SOLDER MASK DETAILS 4214839/E 09/2019 NOTES: (continued) 5. Publication IPC-7351 may have alternate designs. 6. Solder mask tolerances between and around signal pads can vary based on board fabrication site. www.ti.com

EXAMPLE STENCIL DESIGN DBV0005A SOT-23 - 1.45 mm max height SMALL OUTLINE TRANSISTOR PKG 5X (1.1) 1 5 5X (0.6) SYMM 2 (1.9) 2X(0.95) 3 4 (R0.05) TYP (2.6) SOLDER PASTE EXAMPLE BASED ON 0.125 mm THICK STENCIL SCALE:15X 4214839/E 09/2019 NOTES: (continued) 7. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate design recommendations. 8. Board assembly site may have different recommendations for stencil design. www.ti.com

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