HP Calculator Power Supplies -...

HP Calculator Power Supplies

from

HP-35 to HP Prime

Presentedby:JimJohnsonHPHandheldConference2016–FortCollins,CO

September17-18,2016

HP Calculator Power Supplies – HP35 to Prime

Synopsis:Thechallengesofprovidingpowertoahandhelddevicestretchesthedesignersimaginationandcreativity.Firstyoumustprovideenoughpowertolast,atminimum,afulldayofnormalusage(preferablymonthsofuse),poweringalltheIC’sandthedisplay.Secondly,youmustmeetagencyrequirements(i.e.FCC/CE/EMI/RFI/USB,etc).Thirdly,ifthedevicehasrechargeablebatteries,youmustbeabletosafelyrechargethem.Oralternatively,youmustuselowcost,disposablebatteries.Andfinally,thehandhelddevicepcboardmustaccommodatemanysmallpowerconversiondevicesintoarelativelysmallspaceanddothisefficientlyinpcboardcm2,powerandcost.


A WORD OF

This is what could happen if you don’t exercise caution in your power system design

FirereportedlycausedbychargingaSamsungGalaxyNote7

http://www.google.com/url?sa=i&rct=j&q=WARNING+Will+robinson&source=images&cd=&cad=rja&docid=C2VkXmjbcaR3RM&tbnid=6EVwC-PaotzYSM:&ved=0CAUQjRw&url=http://www.greenbookblog.org/2010/11/23/danger-will-robinson/&ei=nXorUofANsGMqgGSrYHQAQ&bvm=bv.51773540,d.aWc&psig=AFQjCNFY5iS7Nnw3Z9IxihkNzme__QLYyg&ust=1378667303065406

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwiVvNq-qIbPAhVLSiYKHVFEBS8QjRwIBw&url=http://www.foxnews.com/tech/2016/09/09/florida-mans-vehicle-catches-fire-after-charging-galaxy-note-7-explodes.html&bvm=bv.132479545,d.eWE&psig=AFQjCNGIVOTqV8yMLV-t9pOERf3yEqiQQA&ust=1473648996003200


PowerBudgetfor:•Displaysandbacklighting•Highpowered,highspeedmicrocontrollers•Wirelesscommunications(WiFiorBluetoothLE)•Wiredcommunications(USB)•Piezotransducers/SounddevicesBatterySizeandWeight:•Smalllithium-ionbatteries(NiCadsinthepast)•SizeversusPower(mAH)versusCostRechargeableversusDisposable•Lithium-ionbatteries•Lithium/ManganeseDioxide(Li/MnO2)–(i.e.CR2032)CostConsiderations:•Chargingcircuitryandcharger•Replacementofdisposablebatteries•Replacementofrechargeablebatteries

PowerConsiderationsforaHandheldDevice


A Brief Word About Batteries


Notagoodendresult

ConsiderationsinUsingLithiumIonBatteries

HP Calculator Power Supplies – HP35 to PrimeBatteryCorrosionHP-19C

AfterCleaning

HP Calculator Power Supplies – HP35 to PrimeWhatKindofPowerSupplies?

HPPRIME

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjsqKL2mIfPAhXC6SYKHZBACawQjRwIBw&url=http://www.bechtel.com/expertise/power/nuclear/&psig=AFQjCNFBV3S4Vw_0zThQnXxwb-uwyMvrCg&ust=1473679123921648

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwiz4Y_jmYfPAhXB4iYKHY64DUIQjRwIBw&url=http://www.ebay.com/sch/Network-Server-Power-Supplies/56090/bn_886981/i.html&bvm=bv.132479545,d.eWE&psig=AFQjCNFJ71i1EdzP6t_kJO-5axm8boXU8A&ust=1473679406163007

HP Calculator Power Supplies – HP35 to PrimeHP-35PowerSupply

PhotoCredit:JacquesLaporteandDanWeed

Schematiccredit:KeesVandersanden

HP Calculator Power Supplies – HP35 to PrimeHP-29CIntegratedCircuitsandPowerSupply

13

2

HP Calculator Power Supplies – HP35 to PrimeComponentsofHP-29CPowerSupply

3.3uF,10vNPNTransistor

NPNTransistor Tankoscillatorcircuit330pfcap.&15uHcoil

68Ω10KΩ 10uF,16v

6.8uF,10v

2.2uF,6v

15uF,10v

2.2KΩ

22uF,10v

330pf

100pf

diodediode

diode

diode diode

HP29CPowerSupplyPCB(DaughterBoard)

2


Tankoscillatorcircuit

Vss=+6.3vdc Vdisp=+4.4vdc

Vram=+6.5vdc

Vgg=-12.5vdcVbatt-IN=+2.4vdc

(switched)

HP-21,25and29CPowerSupply

Schematiccredit:JacquesLaporte


PowerSections

PowerNeedsuC:MultiplepowerrailsMemoryDisplayBacklightUSBChargingCircuit+3.7vdcLithiumIonbattery

HP Calculator Power Supplies – HP35 to PrimeHPPrimeMicrocontroller

MicrocontrollerPowerSupplyRequirements2-DC-DCswitchingregulators4–LDOregulators


HP35 PrimeContrastandComparePastwithPresent

4differentvoltagesVbatt= +3.6vdcVgg= -12vdcVcc= +8.2vdcVss= +6.2vdc

+10differentvoltagesVbatt= +3.7vdcVddalive= +1.2vdcVddarm= +1.3vdcVrtc= +3.3vdcVdda33usb=+3.3vdcVddi_udev=+1.2vdcVddsram= +1.8vdcVdisp= +??Vbklight= +??Vcharger= +3.7vdc

Components2PNPtransistors7diodes1multiwoundtransformerHandfullofpassives

ComponentsMultipleswitchingregulatorsMultiplelowdrop-outregulatorsMultipleinductorsMultipletransistorsMultiplediodesManysurfacemountpassives

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwizpb_9robPAhVTxCYKHQ5RB7MQjRwIBw&url=http://museum.mit.edu/150/28&psig=AFQjCNErECSPDzdUZIOM0jkzKMzJg8YuXQ&ust=1473647418807442


Summary and Conclusions•Ashandheldelectronicsbecomemorecomplex,sodoesthepowersupplycircuitrythatpowersthem.•Storagedevices(batteries)andtheirchargingcircuitshavebeenandarebecomingamoreimportantpartofhandhelddevices.Monitoringthestatusandadjustingthechargeofthelithium-ionbatteryiscritical.•Newerpowerintegratedcircuitswillbemoreefficientandnewwallchargersmustmeetlowpowerregulations

Neverleaveunchargedbatteriesinyourcalculatorsforlongperiodsoftimeorriskbatteryleakage,outgassingandcorrosionofothercircuits.


AcknowledgementsandCredits

1. TonyDuell(UK)–InformationonMoHPCsiteandemailexchangein2012.2. JacquesLaporte(r.i.p.)–HPCalculatorForum(www.jacques-laporte.org/

forum)emailexchangeandthepapers“The‘Woodstock’generation”and“TheHP-35PowerUnit”.

3. MuseumofHPCalculators–(http://hpmuseum.org)4. GeoffQuickfall–EmailexchangeregardingHPcalculators,particularlythe

HP19C.5. DaveColver(UK)–EmailexchangeregardingHP29Cschematics.6. RandySloyer–(www.fixthatcalc.com)emailexchangein2012.7. EricSmith–EmailandpostsonMoHPC.8. KatieWasserman–emailexchangeregardingHP29C.9. WoodbankCommunications,Ltd.–Electropaedia10. KeesVandersanden.Calculator/powersupplywebsite.

PersonalCollection:HP01,HP10bII,HP12C,HP15CLE,HP17bII+,HP19C,HP21,HP25,HP29C,HP30b,HP32E,HP32SII,HP34C,HP35S,HP41CX,HP42SHP45,HP67,HP97,WP34S,HPPrime

http://www.jacques-laporte.org/forum

http://hpmuseum.org/

http://www.fixthatcalc.com/

HP Calculator Power Supplies -...

Documents

Transcript of HP Calculator Power Supplies -...