CPG004 DRV88xx Evaluation Modules (Rev. B) - TI.com

1 User's GuideSLVU361B April2010 RevisedOctober2013 CPG004_DRV88xxEvaluationModulesThisdocum entis providedas a supplementto the drv8802 ,DRV8812,DRV8813,DRV8814,DRV8824, DRV8825,DRV8841and detailsthe hardwareimplementationof the CPG004 DRV88xxEVMC ustomerEvaluationModule(EVM).On thisdocument,DRV88xxwill be usedinterchangeablyto referto any of the CurrentControl(VREFAand VREFB).. MotorSpeedControl(PWM).. StepperMotor(DRV8824).. of INx of Tables1 BVREFD efaultJumperAllocationon a Per April2010 RevisedOctober2013 CPG004_DRV88xxEvaluationModulesSubmitDoc umentationFeedbackCopyright 2010 2013,TexasInstrumentsIncorporatedVM PowerDRV88xxMotor OutputsUSBConnUSB ChipMSP430 AVREFBVREFDECAYP roto AreaWhere DRV88xx stands for one ofDRV8812, DRV8813, DRV8814, DRV8824, DRV8825,DRV8841 or , DRV88xxCustomerEVMoffersaccessto VM (MotorVoltage)powerrail via a terminalblock(J1).

2 Aset of test clipsin parallelwith the terminalblockallowsfor the monitoringof the accordingto :VDDfor logicand microcontrolleris on the DRV88xxdevicehas beenbroughtout to a test labelon the thosepins that changefunctionalitydependingon deviceflavor,a tableis providedwith correspondingfunctionnameon its April2010 RevisedOctober2013 SubmitDocumentationFeedbackCopyright 2010 2013,TexasInstrumentsIncorporated(a)1 From PotFrom DAC(b)(c)25612125656 From AVREFTo configure the BVREF select jumper:(a) Use position JP1-1:2 to select the respective variable resistance potentiometer.(b) Use position JP1-2:3 to select the MSP430 DAC functionality.(c) Use position JP1-5:6 to select AVREF as reference voltage source.

3 This jumpershould not be left open as lack of a reference voltage on the device will minimizecurrent sourcing into the respective H Bridge, resulting in very poor motion orno motion at all.(a)(b)11 From PotFrom DACTo configure the AVREF select jumper:(a) Use position JP2-1:2 to select the MSP430 DAC output (default).(b) Use position JP2-2:3 to select the respective variable resistancepotentiometer. This jumper should not be left open as lack ofreference voltage on the device will minimize current sourcinginto the respective H Bridge, resulting in very poor motion orno motion at only threejumpersthe usermustconfigureas an alternative,a variableresistanceis providedon (JP2)Figure1. (JP1)Figure2.

4 BVREFS electJumperConfiguration3 SLVU361B April2010 RevisedOctober2013 CPG004_DRV88xxEvaluationModulesSubmitDoc umentationFeedbackCopyright 2010 2013,TexasInstrumentsIncorporated(a)(b)1 1 From PotFrom DACTo configure the DECAY select jumper:(a) Use position JP3-1:2 to select the MSP430 GPIO functionality (default).(b) Use position JP3-2:3 to select the respective variable resistancepotentiometer. Allowing the jumper to not be placed, will result in thedevice operating under mixed decay BVREFD efaultJumperAllocationon a Per DeviceBasisDEVICEBVREFJUMPERDEFAULTDRV88 02/12/13/14JP1-3:4 DRV8824/25JP1-5:6 DRV8841/43JP1-3 (JP3)Figure3. two waysof connectingthe differentmotorstyles(singlebipolarsteppe rmotoror two DCmotors)into the CPG004_DRV88xxEvaluationModule:four pin header(J4) and four positionterminalblock(J3).

5 Althoughfeasible,we do not recommendthe connectionof any motorinto the test clipsastheseare Kelvinconnectionsand not ratedfor high April2010 RevisedOctober2013 SubmitDocumentationFeedbackCopyright 2010 2013, FTDIUSBD riverInstructionson how to installthe FTDIUSB driveron a Windowsbasedcomputerare detailedin the file suppliedwith the CD insidethe CPG004_DRV88xxEvaluationBoardWindowsAppl icationSoftwareCopythe contentsof the WindowsApplication folderprovidedwithinthe CD, into WindowsApplicationSoftwareTo run the application,doubleclickthe foundon thesamefolderthe applicationwas WindowsApplicationThe CPG004_DRV88xxEVMW indowsapplicationis the softwarecounterpartfor the allowsthe PC computerto connectto the MSP430F1612microcontrollerthoughan establishedand commandsare sent,microcontrollertakescareof configuringcontrolsignalsand administeringcertainlevelsof automation,suchas microsteppinggenerationfor(DRV8812/13),S TEPand DIR control(for DRV8824/25)or PWMoutput(for DRV8812/13/14/41/43).

6 The graphicaluserinterface(GUI)has beendesignedto allowfor all of the DRV88xxdevice s functionalityto be testedwithouthavingto intervenewith the hardware,exceptfor the properconfigurationof jumpers, followingpicturesshowthe applicationisdividedinto threetabs:one for eachone of the menucontainsitemstoconfigureand enable/disablethe drv8802 -12-13-14 TabThe drv8802 -12-13-14tab containsall the controlsignalsneededto controlmotorenablement(ENABLEA, ENABLEB), directionof rotation(PHASEA, PHASEB) and currentcontrol(AIx and BIx).AccesstobothDACgeneratingVREF analogvoltagesis achievedby of slidersallowthecontrolof PWMduty cycleon ENABLEx is intendedfor simplestepperdemoallowshookinga bipolarstepperto the DRV8812 EVMand haveits speedanddirectioncontrolledby an algorithmwhichmodulatesthe VREF currentin a high functionis achievedby usingbothMSP430 DACoutputsand is only availableif respectivejumpersare set for dual DACconnection(as default).

7 5 SLVU361B April2010 RevisedOctober2013 CPG004_DRV88xxEvaluationModulesSubmitDoc umentationFeedbackCopyright 2010 2013,TexasInstrumentsIncorporatedThe DRV8824-25 GUIThe DRV8824-25has an updatedGUI that containsall the necessarycontrolsignalsfor drivinga controlare enablement,directionof rotation,speed,numberof steps,referencevoltage(for maximumcurrent)and degreesof DRV8841-43 TabThe DRV8841-43tab is very similarto the drv8802 -12-13-14tab, exceptcorrectnamingconventionshavebeenfo llowedto showcasethe AINxpins (insteadof PHASEand ENABLE).In this tab, the four INxsignalshavea respectivePWMsliderin orderto providespeedcontrolper H Bridgeon bothdirectionsper H April2010 RevisedOctober2013 SubmitDocumentationFeedbackCopyright 2010 2013, MenuThe menuat the top of the applicationoffersa seriesof quickoptionsfor how the COMport is to :Exit Terminatesthe applicationSettings:Port SelectsfromCOM1to serialport'sactualport numberdefaultsto whatwe havespecifiedon the.

8 However,any port betweenCOM1 and COM4 are :Opensthe menuitem is pressed,its captionchangesto Disconnect .Disconnect:Closesthe menuitem is pressed,its captionchangesto Connect .Afteropeningthe application,the orderof eventsshouldbe:1. Go to Settings Port and choosethe COMPort wherethe FTDI devicehas beenconfiguredto the COMport is 4, thenthis step can be skipped,as applicationdefaultsto the port is available,the menuchangesthe Connect captionto Disconnect . PressDisconnectto disablethe <1> <0> <0> shouldreturnon the text box as an text box also changesfromred The applicationis readyfor applicationis communicatingwith the interfaceboard,the controlsignalscan be actuatedbycheckingor un-checkingcheckboxeson the will havea differentset of controlsignalsas dependingon the devicebeinginterfaceon.

9 NSLEEPand nRESET controlsignalswill be on controlsignalsis identicalacrossthe checkedcheckboxtranslatesto a HI levelon the a LO levelon the DECAYpin is in realitya GPIO operatesas HI and LO accordingto havethe DECAYpin floating,engagingmixeddecaymode,simplyre movethe April2010 RevisedOctober2013 CPG004_DRV88xxEvaluationModulesSubmitDoc umentationFeedbackCopyright 2010 2013,TexasInstrumentsIncorporatedVREF = DAC_VALUE 4095 The CurrentControl(VREFAand VREFB)If the DRV88xxhas beenconfiguredto acceptVREF analogvoltagesthroughthe microcontrollerDACoutputs(referto Jumperssection),thenthe sliderbar on the CurrentControlframecan be usedto set CurrentControlThe 12-bitDACchannels0/1 are connectedto the DRV88xxVREF analoginputsABVREFand DACdigitalvaluefrom0 to 4095,changesthe analogvoltageat the respectiveVREF pinfrom0 V to V respectively,followingthe equation:(1)Where:VREFis the a numberfrom0 to sliderswill updatethe VREF= xV captionbeloweachrespectivesliderwith the resultof thepreviousequationgivingthe useran idea of whatanalogvoltageis beingpresentedat the MotorSpeedControl(PWM)The drv8802 -14can be utilizedto controlDC the purposeto controlDC motorspeed,aslideris providedwhichappliesa PWMto the ENABLE line.

10 The PWMsliderconsistsof an 8-bitnumberso positionfrom0 to 255 are MSP430directlytransformsthis 8 bit numberinto therespectiveduty DutyCycleIndicator8 CPG004_DRV88xxEvaluationModulesSLVU361B April2010 RevisedOctober2013 SubmitDocumentationFeedbackCopyright 2010 2013,TexasInstrumentsIncorporated%Duty Cycle =PWM 255 100 WindowsApplicationWhenthe sliderbar is movedacross,the DutyCycleindicatoris cycleis an integernumberbetween0 and 100 and it is computedaccordingto the equation:(2)The DRV8841-43will offerthe sameabilityto applya PWMsignalto eachone of the INx PWMS ignalon INx StepperMotor(DRV8824) StepperMotorThe Windowsapplication,in conjunctionwith the MSP430F1612microcontroller,utilizesa seriesof timersto coordinatethe rate of stepssent to the the controlsignalsare configuredaccordingly,(ENABLEn= LO, SLEEPn= HI, RESETn= HI.)