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Preliminary

1. PC V R15 RN Tio 0 01uF C20 V 10kQ U7 F8 Jpwr cc L Vi 1 1 3 3 Ptest 4 Ef IS S A E R S e Vane mE y Pa 3 2 Bae spa Te F2 1 5 95 1 c e aie cc Cig eas ile 2 Vaur V7 l E S NC 1 200mA BW i hr IN IE GND 6 o F3 r ne al S dd R6 4 5 10uF e F9 6Vdc Test
2. X C Brown mmm Brown Rev 1 5 2 26 2004 8 46 00 AM Page 42 of 45 Preliminary 11 0 PGA309DK External EEPROM Settings for Functional Test 8 Bit EEPROM Load gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt PGA309 External EEPROM Configuration Data 8 External EEPROM PGA309 PGA309 Address Internal Register Internal Address Decimal Address Description Data D15 1 0 Programmed Flag Value MSB LSB Must be as Shown 0 3 2 Unused MSB LSB Set to Zero 0 5 4 Unused MSB LSB Set to Zero 0 7 6 MSB LSB 00011 Reference Control amp Linearization 0 7 6 0 9 8 PGA Coarse Offset amp Gain Output MSB LSB 00100 Amp Gain OWD GO2 9 8 0 11 10 PGA Configuration amp Over Under MSB LSB 00101 Scale Limit 0 11 10 i 13 12 MSB LSB 00110 Temperature ADC Control 0 13 12 0 15 14 FFFF sum Hex Eq of each location MSB LSB 1 0 thru13 12 truncated above 16 bits Checksum1 1 8 Bit EEPROM Load gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt gt PGA309 External EEPROM Configuration Data 8 External EEPROM PGA309 PGA309 Address Internal Register Internal Address Decimal Address Description Data D15 17 16 Temperature Index Value MSB LSB TO 0 19 18 Zero Adjustment DAC MSB LSB value for TO and below 0 21 20 Gain A
3. Pressure Input Figure 1 PGA309DK Typical System Setup 3 0 PGA309 Sensor Interface Board Overview Refer to PGA309 Sensor Interface Board Schematic 3 1 Input Output Bridge sensor input connections are made though Tin an 8 position screw terminal strip In parallel with Tin are plated through holes that are provided for solder connections if so desired The connections from the PGA309 Sensor Interface Board to the PGA309 PC Interface Board are provided through Tio an 8 position screw terminal strip This connector provides ease of connections to wires for the required selected signals when placing the PGA309 Sensor Interface Board inside a temperature chamber for PGA309 Sensor calibration In parallel with Tio is Jtest which provides a means for direct plug in connection to the PGA309 PC Interface Board This is useful for initial checkout of the PGA309DK system 3 2 Jumper Configuration J1 J2 J3 J4 J5 J10 and J11 allow flexibility in the configuration of the connection to a bridge sensor These jumpers also allow connection of the on board test resistor Rrest used for testing functionality of the PGA309 without any bridge sensor connected Rt and Rt allow for resistors to be used in the top or bottom of the bridge sensor s excitation path for one method of measuring bridge temperature by total bridge resistance changes Jumper J6 is used to configure the PGA309 circuit for external or internal temperature sensing If exte
4. 2 The Sensor Cuvefit Worksheet Figure 29 is the place where all results of the calibration measurements are entered and the sensor compensation coefficients are calculated The fields colored light blue contain pre selected values such as PGA309 Gain and Offset settings the temperatures where the measurements are made and sensor pre characterized parameters such as span drift non linearity The dark blue fields are the ones where the measured values are entered at each stage of the calibration The framed area is filled out when Prepare Calibration Sheer is clicked on the previous page It contains the cells with calculations specific to the chosen calibration algorithm The two control buttons paste in the current worksheet cell either the last Vout reading or the last Temp ADC value from the Board Control Program This saves the manual typing of the numbers However all the data can be also entered manually if the measurements are made with other equipment than the PGA309DK PC Interface Board Ed Microsoft Excel Copy 3 of PGA309 Calibration xls f S Bf x File Edit View Insert Format Tools Data Window Help Acrobat 2 81 x DRALL Re cA vz 4 zi m E24 0 461 A B C i aoa E G H J K p 1 PGA309 Calibration algorithm 2 The target sensor approximation equation 3 Uses 2nd order quadrature equations for pressure non linearity and temp drifts of offset and span 4 Kbridge P T ko0 ko1 T ko2 T
5. Cfqz OverUnder Cas ADC QutEnbl Counter X larmstatus RO Contig Checksum Fine Gain DAC VPE 0x1611 01603 0x0001_0110_0000_0011 Ox0000 O lt 0000_0000_0000_0000 Ox0000 Ox lt 0000_0000_0000_0000 OxF056 Ox0111_0000_0101_1011 Register Bitmap RFE RFE ILK CFG1 LE CFGL EXTEM INTEM EXTPOL INTPOL b bp b b R b Rh B S RFB OUEN HL2 HL1 HLO LL2 LL1 LLO ensis m J h 0 o 3 n n n FE Reserved Factory Bit Set ta zero for proper operation Write EEPROM Read EEPROM Enable Internal vret w Vref Value 4 096 ho Fault Detection Detect External Faults Detect Internal Saturation Vout high on external fault Vout high on internal fault PSA309 Temp ADC Convert Interface Board and ADS 1100 Supply Vcc VY 15 0 vol 4 03900 Dec 26470 Hex LS 14 ADC Config d FE Reserved Factory Bit Set to zero for proper operation LK CFG 1 O0T Clocking scheme for front end PGA auta zero and Coarse Offset DAC Chopping XTEM Enable External Fault Comparator Group UNB M INR Eo IM Ec INN Al 1 Enable 0 Disable MTEHM Enable Internal Fault Comparator Group 82547 Lo 42547 Hl amp 1S amp T LO amp 1S amp T HI 43_VCM 1 En Dshl XTPOL Selects YOUT output polarity when External Fault Comparator Group detects a fault rif EXTEM 13 1 Force WOUT high D Force OUT low MTPOL Selects YOUT output polarity when Internal Fault Comparator Group detects a fault tit INTEM 14 1 Force WOUT
6. File Edit View Insert Format Tools Data Window Help Acrobat e x OSE BIS6RY SBAS h o Br eAA Mam G 10 B z amp amp 5 A Im e Q ao A B 4 D J E 1 F a j HW j 4 gi L M N E RES S B 1 PGA303 Desired output and its look up table E 2 Lookup Table Parameters Resulting Look up Table 3 Enter Output Scale of points Point Temp Gfine v v GainSlope Vzero V amp Vout mas v Ntempz 1 0 681061 0 3552442 5 Vout mins Y Optional 2 375 0 68821 0 000572 0 3494514 0 000543 FB32 amp LUT Tmind 509 degC 3 25 0 635514 0 000584 O 3416586 0 000543 FESC Ig LUT Tmas degC 4 12 5 0 702373 0 000537 10 3349658 0 000543 0185 8 5 0 0 710593 0 00061 0 3280731 0 000543 O4 AF BER 6 125 0 718381 0 000623 0 3212803 0 000543 07 D9 7 25 0 726341 0 000637 0 3144875 0 000543 0B02 8 375 0 73448 0 000651 0 3076347 0 000543 OE2C re 3 50 0 742803 0 000666 03003018 0 000543 1156 13 10 62 5 0751317 0 000681 0 2941092 0 000543 1450 14 t 75 0 760028 0 000637 02973164 0 000543 173 15 12 87 5 0769344 0 000713 0 2805236 0 000543 1AD 3 16 13 100 0 778071 0 00073 02737308 0 000543 TDFD 17 14 12 5 0 78748 0 000748 0 266338 0 000543 2126 S 15 125 0 796992 0 000766 0 2601453 0 000543 2450 13 16 137 5 0 806801 0 000785 0 2533525 0 000543 277 A 20 17 150 0 816855 0 000804 0 2465597 0 000543 243 21 0 816855 0 0 2465537 Vout max and min calibrated
7. 23 125 degC 172 I DC Config Convert is D i Figure 16 Internal Temperature Reading If all steps above in Section 6 have been successfully completed then the PGA309 Sensor Interface Board PGA309 PC Interface Board PC Cable PGA309DK Board Control Software are all operating correctly Rev 1 5 2 26 2004 8 46 00 AM Page 21 of 45 Preliminary 7 0 Board Control Software Overview Figure 17 depicts the Main Window for the Board Control Software Subsections of the Main Window outlined by dashed lines as well as the Top Row Control Buttons and Board Communication Status will be described in detail in sections 7 1 7 10 Texas Instruments PGA309 Designer s Kit Control Program File Edit Bench Setup B E mi EE Top Row Reset Open File Save File Detect Write PGA309 Read PGASOS Write EEPROM Read EEPROM _ Control Buttons_ PRG pin shortedto Vout PGA308 Test Pin HIGH EE ne n shorted to Vot ext Pin j eee a ee A 1 E nViogoo lt Enable internal wre PGA309 Regist 1 S Frontend PGA Gain V V T4990 wret Value 5 0 Click an the register to edit the value and see the details Ti Fat S S Fl Fine Zero DAC vy s Brar Vk rr Detect External Faults r ADC Out RO O lt 0000_0000_0000_0000 Fine Gain DAC V V 333 333m Detect Internal Saturation T ZeroDAC Oxo0000 0000 mann nono j a Output Amp Gain pehe Ran Vou High on pd fault
8. Cancel Places Open as read only Figure 18 Typical Write PGA309 or Read PGA309 Pop up Window 7 2 EEPROM Lookup Table When the EEPROM Lookup Table is selected on the bottom Tab in the Main Window the Temperature Coefficients stored in the PGA309 external EEPROM from the last Read EEPROM are displayed in the Lookup Table section of the Main Window These values can be displayed by selecting the desired format as Binary Hex or Decimal under Display Mode in the Lookup Table section See Figure 17 If the entire contents of the EEPROM is to be viewed or edited in Hex and ASCII only then click on Show 1kBit EEPROM in the Lookup Table section of the Main Window Figure 16 shows the resultant pop up window which displays the entire external PGA309 EEPROM contents in Hex Remember the EEPROM contents are mapped least significant byte first relative to PGA309 16 Bit registers as shown in Figure 20 PGA309 Board 1 KBit EEPROM Content Siz Addr Hex ASCII 19 54 00 00 00 00 00 05 Close 11 16 47 0A 03 16 5B 70 00 08 40 06 FF FF FF TF edi 00 00 C1 71 FF FF FF FF X eee FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF Read EEPROM FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF 104 FF FF FF FF FF FF FF FF IIZ FF FF FF FF FF FF FF FF 120 sd FF FF FF FF FF FF FF Figure 19 PGA309 Exte
9. 0 0000 V Tmax Vexc 3 400 V with LinDAC 0 Troom Insert TempADC reading in active cell Insert Vout reading in active cell 6 0E 02 Tei Figure 34 Top Part of the Curvefit Worksheet 3 Update the Temp ADC reading in the Board Control Program by clicking Convert in its Main Window see Figure 35 Return to the Sensor Curvefit Worksheet highlight the cell C18 ADC read Tmeas1 and click the button Insert Temp ADC Reading Figure 36 Figure 35 Board Control Software Main Window Convert Button Rev 1 5 2 26 2004 8 46 00 AM Page 38 of 45 Preliminary Insert TempADC reading in active cell Insert Vout reading in active cell step 4 Measurement Conditions P 96 GainDAC ZeroDAC _ VoutiMeas RTI Kbrg v v 3TISpan V V step 5 27 0 0 6660 0 3160 q 2 48E 03 27 0 0 6660 0 0000 Note needed to correct for ZeroDAC errors 2 77E 02 5 27E 02 5 026E 02 27 50 0 6660 0 3160 27 100 0 6660 0 3160 Figure 36 Entering the Values for Tmeas1 and Vout Tmeas1 4 Apply the Pressure Pmin to the sensor Make sure the PGA309 output is enabled and click Update Vout see Figure 37 in the Board Control Program or measure Vout using a voltmeter Return to the spreadsheet highlight the cell E24 VoutMeas 9 Pmin Tmeas1 and click the button Insert Vout Reading or enter the measured voltage by hand Figure 36 Im Figure 37 Board Control Software Main Window Upd
10. Autocalc Chksum box is checked then both the configuration register part checksum Checksum1 and the temperature coefficient part checksum Checksum2 for the external EEPROM are computed automatically after every change If the box is not checked then the calculations of the checksums may be manually accomplished by pushing the Update Checksums button or entering the checksum values directly from hand calculation The Keep comm alive box when checked reads the Temp ADC register and updates the Main Window reading about every 0 75 second depending upon the operating system used This will prevent the 1s timeout in the PGA309 from expiring thus stopping EEPROM read back updates even if Test Pin is set low The Instant Update box when checked updates the PGA309 Registers immediately after every bit change without having to push the Write PGA309 button Remember that unless Test pin is set high these settings will be overwritten by valid external EEPROM data Keep comm alive Instant Update Autacalc Chksum w Update Checksums Figure 25 Updates Section Rev 1 5 2 26 2004 8 46 00 AM Page 30 of 45 Preliminary 7 9 Board Communication Status The Board Communication Status section see Figure 26 is located in the bottom left corner of the Main Window When reads or write to the PGA309 internal registers or PGA309 external EEPROM are executed messages will appear in this window as confirmation that the communication
11. B 26 0 52 4 52 28 0 515 4 515 30 0 51 451 ETT 0 505 4 505 45 Cal dvoutmin Cal dvoutmas 3 0 435 4 495 p a Yout Y o tn 049 449 42 0 485 4485 44 0 48 4 48 45 50 30 10 10 30 50 70 30 110 130 150 Temp degC mum Ready md LI TL cNME DL Iz Figure 31 Calibration Results Rev 1 5 2 26 2004 8 46 00 AM Page 36 of 45 Preliminary 4 The remainder of the worksheets contain the templates of the curve fitting algorithms and back ground calculation data 8 4 Step by Step Calibration Using PGA309 Designer s Kit 1 The PGA309DK Sensor Interface Board with a sensor or a custom module are initially configured as described in Section 8 2 It is measured at the first usually the room temperature 7meas7 and at either 2 or 3 pressure levels see Section 8 1 The output should be within the adjustment ranges of the Zero and Gain DACs It is important to enable the EXTEN and INTEN bits and or read back the Alarm Status Register 8 to see if any of the external or internal comparators raised a flag indicating either sensor fault or an internal signal path saturation In case of a fault or an unsatisfactory output signal range the coarse settings must be adjusted and the measurement repeated After a valid output range has been achieved the following settings must remain fixed Reference and Excitation Level B Coarse RTI Offset B Coarse Front End and Output Amplifier Gains Temp A
12. GainDAc Ox0000_ nop 000 0000 rt M OUT hiah on internal faul m Ref amp Lin Ox0000_ manae _0000_0000 Owverzcale Limit HEES E 21 oec E mg Underscale Limit Dec le Hex sacco lli Convert Enable Sensor Excitation I Gein Vos Cg Cfgz OverUnder Ox 0000 nano nob Ctg3 ADC 0x0000 0000 0000 8000 OutEnbl Counter ox B00 noon nono onn AlarmStatus RO ox0000 Ox0000_0000_0000_0000 vexe A f Contig Checksum x amp BB6 0x1010_1011_1011_0110 Linearization Coet MI ponere e eu oec e eue a E Eu T Lookup Table Interface Board and ADS1100 ly i oe poe a H nable Over Under Scale Limits amp TFFF 0000 8000 Display Mode Binary C Supply Yoo vy 5 0 Hex S Vol 163992 Decimal Y p Dec 26476 SSS Keep comm alive j PEA Interface 4 Two Instant Update H Ivvo VVire OneAMre Autocalc Chksum w Show 1kBit EEPROM Update COM Port Checksums Setup O rr pep mn l e ee Board l IEEPROM Lookup Table Bitmap of a register Board Communcation Idle Board Communication Status Figure 17 Main Window Rev 1 5 2 26 2004 8 46 00 AM Page 22 of 45 Preliminary 7 1 Top Row Control Buttons The Top Row Control Buttons are described in Table 5 Button Name Heset Resets all r
13. 1 5 2 26 2004 8 46 00 AM Page 18 of 45 Preliminary 2 Select PGA309DK Test txt and open this file on the PGA309DK CDROM A pop up window will appear as in Figure 13 Click on OK RENI IN LN MB a MA MAA MMA LOUROLORO MAMMA LAMA V E LIGA E81 ST ee lt P es MT a ELST a eee TR RPM E ALAR ia R hd Pe e a VI eT du el e 1 PGA309 Designer s Kit The File CHPGA309 XTR1USPGA3O0S FinaliPoas09 EVMIPGSAS09DE CD Sw Rev 1 0 71 PGASUSDK Test txt has been succesfully loaded OK Figure 13 Open File Acknowledge Pop up Window The Main window will appear as in Figure 14 al x 4 Texas Instruments PGA309 Designer s Kit Control Program File Edit Bench Setup D E S 83 ur nu 9 e Reset Open File Save File Detect Write PGA309 Read PGA309 Write EEPROM Read EEPROM PRG pin shorted to Vout 7 PGA309 Test PinHIGH JY EG ADR N y Drtei L sah Ld Be aE AS ee Input Referred Offset MVJ_3977m lt Enable Internal Vref IV PGA309 Registers l E 4096 Click on the register to edit the value and see the details O POS Gn CUT dea 000 2 eh NUS J Fault Detection Fine Zero DAC V f100 000m Detect External Faults ADC Out RO Ox01B4 0x0000_0001_1011_0100 Fine Gain DAC V V 999 990m Detect Internal Saturation ZeroDAC 0x0640 0x0000_0110_0100_0000 i Output Amp Gain V V we Vout high on uen fault GainDAC OxFFFF 0x1111 1111 1111 1111 i Yout high on internal fault LS 14 Ref
14. 2 ko3 p ko4 p 2 I T ko5 T ko6 T 2 5 B Fill out the highlighted cells PGA309 non variable during calibration settings 7 Pressure values Initial settings of the Fain Adjust DACs 8 Pmin Vref GainDAC1 hex gt gt 0 6660 V V 9 Pmax Kexc ZeroDAC1 hex gt gt 0 3150 V 10 Gfront Alternative 11 Temp range Gback settings of Gain and ZeroDACs GainDAC2 hex gt gt 0 3333 V V 12 Tmin VosRti ZeroDAC2 hex gt gt 1 3400 V 13 Tmax Vexc 3 400 VY with LinDAC 0 14 Troom 15 Insert TempADC reading in active cell Insert Vout reading in active cell pADC Reading T meas Tmeas1 Tmeas2 21 22 Measurement Conditions Measured Data 3 23 P GainDAC ZeroDAC VoutMeas RTI Kbrg vN TlSpan V v S 24 0 0 6660 0 3160 248E 03 A 25 0 6660 1 3400 Note needed to correct for ZeroDAC errors 26 50 0 6660 0 3160 2 77 E 02 2 27 100 0 6660 0 3160 5 27E 02 5 026E 02 K 28 100 0 3333 0 3160 To correct for GainDAC errors gt U 0 6660 0 3160 2 74E 03 gt 30 100 0 6660 0 3160 5 04E 02 4 77 E 02 3j 31 LG 32 Characterization Data 2 33 GainTCNonlin T of Span Tmeast 34 OffsetTCNonlin of Span Tmeas1 ETA I4 lt gt MIN Main Sensor Curvefit Calibration Results Z Template2T 3P Z Template2T 2P Z Temr Ready ps pem fe fessi ota free Den 1 0 Figure 29 Sensor Curvefit Worksheet Rev 1 5 2 26 2004 8 46 00 AM Page 35 of 45 Preliminary Upon completion of the
15. 7FFF 0000 o 100i E GM Vout max and min calibrated Figure 38 Calibration Results Worksheet 10 Return to the Main Worksheet and click on the Save Register Lookup Table button to save the calibration results in a file Now load this file to the PGA309 EEPROM using Board Control Program by using the Open File button and then the Write EEPROM button 11 Verify that the output of the PGA309 is satisfactory 12 Optional To account for the offset and gain errors of the PGA309 ZeroDAC and GainDAC two additional measurements might need to be performed after Step 4 and Step 5 correspondingly This should improve the calibrated output precision A After Step 4 while Pmin is applied to the sensor adjust the value of the ZeroDAC and measure the output of the PGAS309 Select a ZeroDAC value that does not saturate the signal path while giving you a largest Vout change Enter the ZeroDAC hex value in the cell 112 and the Vout reading in the cell E25 or E26 depending on the template used This calculates a ZeroDAC correction factor in the cell 137 Return the Zero DAC to its original value B After step 5 while Pmax is applied to the sensor adjust the value of the GainDAC and measure the output of the PGA309 Select a GainDAC value that does not saturate the output amplifier while giving you a largest Vout change Enter the GainDAC hex value in the cell I1 1 and the Vout reading in the cell E28 or E29 depending on the temp
16. Gain V V ue VOUT Ae on Se fault GainD Ar Ox4000 0x01 00_0000_0000_0000 ET out high on internal fault Ref amp Lin Ox0500 Ox0000_0101_0000_0000 Enable OvertUnder Scale Limits I PGA3US Teme ADC Gain Vos Cig 0x1611 Ox0001_ 01100001 0001 Oyverscale Limit 13 976 d Dege degt ciga OverUnder OxO44 Ox0000_1010_0100_0111 Linderscale Limit gt 47 308m T b Cas ADC Ox1603 00001 0110 _0000_ 0014 OutEnbl Counter Ox0000 Ox0000 0000 0000 0000 Enable sensor Excitation IV H 0000 0000 io e ex ue AlarmStatusr RO Ox0000 Ox0000_0000_0000_0000 3 400 bul Conen Config Checksum 0x056 0x0111_0000_0101_1011 Linearization Coet v y 0 000 Lookup Table PRG pin shorted to Vout X PGA3D08TestPin HIGH T T5818 Interface Board and ADS 1100 0200 0644 FFFF Display Mode TFFF Oooo Tic Binary Supply vec vy 5 0 Hex fe Decimal Soo tex am Board Discard Update Vout Settings Keep comm alive ir PA Interface TwsaMre C Instant Update LM HE Checksums One wire Show 1kBit Autocalc Chksum jv 7 EEPROM Update COM Port Setup i EEPROM Lookup Table Bitmap of a register Foard Communcation Idle Figure 8 Software Startup Main Window Rev 1 5 2 26 2004 8 46 00 AM Page 16 of 45 Preliminary 6 5 3 Software Board Communication Setup Manual COM Port Setup If on initial software startup the right Com port is not selected automatically
17. Messenger m Accessories Fi Adobe f Autodesk WHIP Fi BusinessObjects 5 1 D Cisco Aironet m Cisco Systems FT Cisco Systems VPN Client F Dell Accessories Fi Evidence Eliminator Fi Exceed E FinePrint pdfFactory an Games e IBM techexplorer Hypermedia Browser Ff Intervideo WinDVD ig iPass m Mathsoft Apps FT Microsoft Office Tools E Modem Helper an netDeploy 4 5 e Netscape Communicator m Norton AntiVirus Corporate Edition Fi Oracle for Windows NT Preliminary la PGA309 Designer s Kit f PGASOSEYM Test Program f Real e Remote Automation Management ie Roxio Easy CD Creator 5 ie Startup Fi TI Backup m TIFTP Ej TI COMM for Windows fr User s Guides ie VisSim Comm 4 5 Documentation Fi VisSim Comm 4 5 Software ie VisualSpicePro f winzip fan xnview I Yahoo Messenger Fi Zone Labs 73 Acrobat Reader 5 1 d DESKTOP INI 4B Internet Explorer 7 Microsoft Access 2000 Microsoft Excel B Microsoft Outlook s Microsoft PowerPoint Microsoft Visio Microsoft Word WS MSN Explorer NetMeeting Outlook Express E PeoplePC Online r Remote Assistance 89 Solution Center Texas Instruments ESP 2 Figure 6 PGA309DK Board Control Software Startup Hev 1 5 2 26 2004 8 46 00 AM Calibration Spreadsheet 5 PGA309 DK Board Interface Page 14 of 45 12 41 PM Preliminary 6 5 2 Software Board Communication Setup Default O
18. Two Wire masters PC and PGA309 sharing the bus It is recommended to have PRG wire connected on the PGAS309 Sensor Board even when using Two Wire communication The Board Control Software addresses PGA309 using One Wire interface prior to closing the switches U10 U11 This stops any activity by the PGA309 on the Two Wire interface for 1 second and prevents any bus conflicts By pushing the COM Port Setup button a pop up COM Port Setup window will appear in the Main Window In the pop up window the desired interface may also be selected as well as which PC COM port Port will be used and the Baud Rate Baud Rate for Communication through the selected COM Port Drop down menus are used to select both the desired COM Port and Baud Rate Once the interface is selected it may be tested by pushing the Apply Detect button or by pushing the OK button in the pop up window LL zear Sa Hex RE in COM Port Setup ka Il Board Update Vout Settings Select Serial Port Interface Port H CD Y zwi T Keep comm alive gE PS Interface Two Mre C Baud Rate 19200 Twie Instant Update One AMire i Autocale Chksum w Apply Detect Cancel Update COM Port Checksums Setup Figure 24 Interface Section and COM Port Setup Pop up Window 7 9 Updates The Updates section see Figure 25 in the Main Window provides options for how certain calculations and readings in the Main Window are updated If the
19. Vcc V box in the Main Window or enter this voltage into the Vs box in the pop up window After these two ADS1100 calibration steps are complete the ADS1100 is fully calibrated for both gain and offset errors Each time the Calibrate ADS1100 Button is pushed a new ADS1100 offset calibration is performed and the subsequent readings will use the latest calibration numbers If the Read ADS1100 button is pushed a single conversion will be performed in the ADS1100 The reading will be updated in both the Main Window and in the pop up window If the box labeled Read ADS1100 Continuously is checked then both the pop up window and Main Window ADS1100 readings will be updated about every 2 seconds depending upon the operating system conditions The ADS Output Register section in the pop up window is a read only bit readout of the latest ADS1110 conversion The ADS1100 Configuration Status Register bits allow for custom configuration of the ADS1100 These bits are toggled by a one click method in the corresponding box The default setting is Ox8C This configures the ADS1100 for Continuous Conversion Mode Internal PGA x1 and 8 samples per second data rate If these settings are changed they can be returned to the initial power up settings by pushing the Gen Call Reset in the pop up window TT the Vcc voltage on the PGA309 PC Interface Board is changed then the ADS1100 will need to be re calibrated for gain and offset this assumes Vc
20. amp Lin 0x0500 0x0000_0101_0000_0000 Enable Over Under Scale Limits Ta az PGA309 Temp ADC Gain vos Ctg1 0x1611 0x0001_0110_0001_0001 Overscale Limit 3 976 Degc 27 25 degC Cfg2 OverUnder 0x0000_1010_0100_0111 Underscale Limit 547 808m Cfg3 ADC 0x1603 0x0001_0110_0000_0011 OutEnbl Counter Ox0000 Ox0000 0000 0000 0000 Enable Sensor Excitation Iv AlarmStatus RO 0x0000 0x0000_0000_0000_0000 Vexc 3 400 v Config Checksum x705B 0x0111_0000_0101_1011 Linearization Coef YA 10 000 Lookup Table 0640 FFFF Display Mode 0000 T1C1 Binary C Supply Yee Vy Hex e Volt Decimal Board Update Vout Settings PGA Interface TwoAMre C Dec ADC Config Convert im d Interface Board and ADS1100 msn D T x o Keep comm alive Instant Update M One Vire Show 1kBit Autocale Chksum Iv i EEPROM Update COM Port Checksums Setup i EEPROM Lookup Table Bitmap of a register Board Communcation Idle Figure 14 Main Window After Open File PGA309 Test txt Rev 1 5 2 26 2004 8 46 00 AM Page 19 of 45 Preliminary Table 3 defines the PGA309 settings defined by this file PGA309 Test txt X0 83 Vref Enabled Coarse Offset 3277mV S S PGAGan X64 J Jl FneGan X1 J A J l 49 J Ou
21. but PGAS09 is not powered up FF gt Lookup Table ad The Sensor interface Board will be powered up erface board and ADS1160 TFFF 0000 2000 Do you want to load the EEPROM and register contents into Ehe PE memory M Supply Ref v l Mo Show 1kBit Hex EEPROM EVM r Interface TwoMWie C Keep comm alive T Instant Update Autocale Chksum Iw Update Port Setup Checksums One wire i EEPROM Lookup Table Bitmap of a register E etecting PEGASO board Please stand by hoc cpad iy p i Figure 7 Software Startup Main Window and First Pop up Window Rev 1 5 2 26 2004 8 46 00 AM Page 15 of 45 Preliminary The First Pop Up Window will disappear and the Main Window should look as in Figure 8 If it does then proceed to Section 6 5 4 and skip Section 6 5 3 3 Texas Instruments PGA309 Designer s Kit Control Program E ull File Edit Bench Setup D Z E ay 90 S 9 Reset Open File Save File Detect Write PGASOS Read PGA309 Write EEPROM Read EEPROM PGA Settings Input Referred Offset mV1 3 2T7m Enable Internal wret w PGA309 Registers 4 096 T Frontend PGA G Ye Vret Val Click on the register to edit the value and see the details REM an VI 164 900 m mss r Fault Detection Fine Zero DAC sy 2 v alee Detect External Faults ADC Out RO Ox0000 Ox0000_0000_0000_0000 Fine Gain DAC WNT 500 000 Detect Internal Saturation ferobac Ox4000 Ox0100_0000_0000_0000 Output Amp
22. e Ns SN74LVC1G66 S 10kQ V EE GND EN 6 db zac lu 200mA Vs je e Hm e Vs S de a ZXMP3A17E6 C11 7 X 18 2kQ dm ee R12 7 E PRG e S F6 E e 190uF i R10 SO 8 0 1uF Ts AGND 6 F17 Vs IPU R14 5V 11 5KQ 4 5 SN74LVC1G07 Vout e F7 Y l e SCL 2000 2 US en VV V9 CC a g 1208 irs R3 Anpu 9 Y SCL t oc Vout e SUE ET vm cio a 6 e S L JC R 3 Vv ootur JC Z E e o pee Vas l scl C15 SDA 0 01nF SDA R17 2 3 j 2000 SN74LVC1G66 5 i V SN74LVC1G07 1206 cis t ie ea m S MEME Ns 9 6 4 5 3 n SDAN o U2 R2 z C Ox a Voc lz NC 20097 T 1Wour 5 3 e PRG L IN V f NC e e PRG vV ed M e T El SRM 6 V E 150uH 0 1 uF 0 01 pF ADS1100 om 1 i C17 FE Ez M Vy Yoo Se D aun C1 n 1 View XS 3 Vos T Texas un 1 5uF 3 Texas Instruments Vcc 0 22uF C6 U3 SDA e Instruments l 4 MAX3238 SEE 0 1uF 7 PCF8574A V le1 Lcd GND Ld od C4 14 5 L au L LAAN BGL Pilg as 24 pnt R1 e SDA 2000 A0 P3 Z OP3 V 2in4 US p48 age P510 5 23 o 13 NT Pei ES F lt DOUT2 DIN2 D ua 4 OO0tuF 1kQ t E 7 22 DIN3 DOUT3 ae ae S V F10 RTS z cc Ppc 4 2 R4 R5 RJ 45 F44 RINI ROUT 1kQ S 1kQ DTRI o 4 1 1206 1206 CTS o 8 ees RS 232 Port 23 D1 G ean D2 RD 7 v4F11 e gt RIN2 ROUT2 Logic I Os n A p RISL748 rAF15 Vec Vs TD 6 pF 12 uli Le DSR 9 fe 10 19 s1 GND Ve
23. in the upper left area of the Main Window 7 6 PGA309 Temp ADC In the PGA309 Temp ADC section of the Main Window the current Temp ADC reading will be displayed if the Convert button is pushed If a continuous update of the Temp ADC contents is desired it can be read and updated about every 0 75 second by checking the box labeled Keep Comm Alive in the lower right corner of the Main Window Please note that this will also prevent the 1s timeout in the PGA309 from expiring thus stopping EEPROM read back updates even if Test Pin is low By clicking on the ADC Config button a pop up window will be displayed as shown in Figure 22 The flexible Temp ADC can be configured as desired for the application For details of the Temp ADC options and settings see the PGA309 Data Sheet If the settings are changed and to be applied then click OK in the pop up window Remember if you do not want the register settings in the PGA309 to be over written by valid PGA309 external EEPROM data then ensure the PGA309 Test pin is set high by checking the PGA309 Test Pin HIGH box in the upper left area of the Main Window If these changes are to be included in the EEPROM then set the Test pin HIGH while configuring the Temp ADC then Write EEPROM then set Test pin low for continuous EEPROM reads by the PGA309 with the new Temp ADC settings Vref Value 4 096 x Fault Detection Detect External Fautts Detect Internal Saturation YOUL high on external fau
24. is taking place successfully EEPROM Lookup Table Bitmap of a register Board Communcation Idle Jp at ee Figure 26 Board Communication Status Section 7 10 Miscellaneous Main Window Boxes In the upper left corner of the Main Window under the Top Row Control Buttons there are two check boxes as shown in Figure 27 PGA309 Test Pin High if checked will put a logic high on the Test pin See Table 6 for the description of the Test pin function LED D2 on the PGA309 PC Interface Board will be lit whenever this box is checked Logic High If the PGA309 is to be configured with its PRG pin tied to Vout then the box labeled PRG pin shorted to Vout see Figure 27 must be checked for reliable operation With this box checked the Board Control Software will cycle power on the PGA309 each time it tries to communicate with PGA309 over One Wire interface to ensure that Vout is in high impedance on the PGA309 during the first 25ms after power up C pu mi 33 n Reset Open File Save File Detect write Pr3A3 PRG pin shorted to Vout PGAsUSTestPin HIGH Figure 27 Miscellaneous Main Window Boxes Rev 1 5 2 26 2004 8 46 00 AM Page 31 of 45 Preliminary 8 0 PGA309 Sensor Calibration Spreadsheet for Microsoft Excel The PGASO9DK includes a Microsoft amp Excel spreadsheet that provides a way to perform a calibration of the sensor module PGA309 sensor The spreadsheet contains two parts Sensor Curve Fit
25. measurements the fitted sensor function is displayed on two plots located on this worksheet see Figure 30 offset and span vs temperature and Vbridge vs input pressure Bridge sensitivity vs temp Kbridge vs pressure Troom 6 0E 02 6 0E 02 5 0E 02 gt 5 0E 02 gt 2 3 4 0E 02 gt 4 0E 02 i o o 9 3 0E 02 Offset 5 3 0E 02 5 Span gt B o gt S 2 0E 02 E 2 0E 02 d 2 S E 1 0E 02 0 0E 00 A 50 50 100 150 0 10 20 30 40 50 60 70 80 90 100 Temp degC Pressure Figure 30 Approximated Sensor Curves 3 The third worksheet is called Calibration Results see Figure 31 It contains the calculated lookup table based on the curve fitting coefficients from the calibration measurements The blue fields are for the user data with the desired output voltage scale compensation temperature range and the number of the lookup table points needed The framed cells contain the messages about the validity of the calculated values whether the DAC and Temp ADC values are in linear range achievable by PGA309 at all temperatures and the Table is arranged properly The plot on the bottom shows the expected PGA309 output vs temperature at zero and full scale output signal Ed Microsoft Excel Copy 3 of PGA309 Calibration xls Bl x
26. screw terminal inputs on Tpwr U7 provides a regulated power source of either 3V or 5V selectable through JA D3 provides protection from inadvertent reverse polarity connections on Jpwr or Tpwr 4 2 Port Expander Configuration Control U5 is an 8 bit serial port expander PCF8574A which allows user control over the configuration of the PGA309 PC Interface Board D1 and D2 are controlled by the Board Control Software and are used as diagnostic LEDs Q1 also controlled through U5 provides a mechanism to turn power on and off to the PGA309 Sensor Interface Board by the Board Control Software This is key when PRG is connected to Vout on the PGA309 since Vout is set to high impedance on power up for 25ms to allow for One Wire communication An unused port P3 pin 7 is available for customer use with control provided in the Board Control Software The One Wire pull up resistor R3 can be disabled through U5 to remove loading from the PGA309 Vout pin for an accurate readout through the ADS1100 U3 U5 also controls the zero calibration of the ADS1100 The Two Wire interface can be isolated from the PGA309 Sensor Interface Board by software through U5 control of U10 and U11 or also by hardware jumper programming 4 3 One Wire Digital Interface On this Designers Kit the One Wire digital interface is the preferred mode of communication with PGA309 It is provided through the conversion of RS 232 UART signals from U9 into open drain output through U2 The re
27. separate from the Vout pin of the PGA309 Disable the Two Wire interface on the PGA309 PC Interface Board and use the One Wire Interface Disabling the Two Wire interface keeps communications to the PGAS309 PC Interface port expander PCF8574A and A D Converter ADS1100 from being delayed by the PGA309 talking to its external EEPROM if PGA309 is in Stand Alone Mode Communication on the One Wire interface will always be recognized and will stop PGA309 to external EEPROM communication 2 For final production testing on 3 terminal sensor modules Vcc GND Vout where PRG is tied to Vout use the One Wire hardware pull up on the PGA309 PC Interface Board for reliable logic level transitions 3 Upon initial receipt of the PGA309DXK first perform the Initial Setup and Checkout as described in Section 6 0 If there is ever a doubt as to proper functioning of the PGA309DK return to this configuration and use Section 6 0 to verify proper operation Next configure the PGA309 Sensor Interface Board with your Sensor for evaluation Connect the PGA309 Sensor Interface Board to the PGA309 PC Interface Board using wire to connect the required signals together If all tests pass then move the PGA309 Sensor Interface Board into the temperature chamber for PGA309 Sensor calibration 4 When Reading and Writing to the PGA309 through the Board Interface Software push the desired button in the Main Window ONE TIME and wait until the Board Communication Status re
28. terms and conditions of sale supplied at the time of order acknowledgment TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with Tl s standard warranty Testing and other quality control techniques are used to the extent Tl deems necessary to support this warranty Except where mandated by government requirements testing of all parameters of each product is not necessarily performed TI assumes no liability for applications assistance or customer product design Customers are responsible for their products and applications using TI components To minimize the risks associated with customer products and applications customers should provide adequate design and operating safeguards TI does not warrant or represent that any license either express or implied is granted under any TI patent right copyright mask work right or other TI intellectual property right relating to any combination machine or process in which TI products or services are used Information published by TI regarding third party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof Use of such information may require a license from a third party under the patents or other intellectual property of the third party or a license from Tl under the patents or other intellectual property of TI Reproduction of information in TI data books or
29. 2 31 32 40 41 42 43 Please read and familiarize yourself with the PGA309 Data Sheet and PGA309 User s Guide prior to using the PGA309DK Designer s Kit since the PGA309 features and modes are not described herein Refer to Texas Instruments Website for latest revision of PGA309 Data Sheet and PGA309 User s Guide http focus ti com docs prod folders print pga309 html PGA309DK User s Guide and PGA309DK Software http focus ti com docs toolsw folders print pga309dk html Rev 1 5 2 26 2004 8 46 00 AM Page 2 of 45 Preliminary 1 0 PGA309DK Parts List PGA309 PC Interface Board PGA309 Sensor Interface Board PC Cable 8 position RJ45 Plug to 9 position female DB9 AC Wall Adapter 120Vac RMS 60Hz in 6Vdc 200mA out USA Shipments Only PGA309DK Software CDROM Rev 1 0 7 or newer PGA309 Designers Kit Board Control Software PGA309 Calibration Spreadsheet for Microsoft Excel PGA309DK User s Manual 1 1 PGA309 Designer s Kit Board Control Software Operating System Compatibility The Board Control Software runs on Win98 Win2000 and WinXP Consult factory for other operating systems 1 2 PGA309 Calibration Spreadsheet for Microsoft Excel Operating System Compatibility The Calibration Spreadsheet runs on Microsoft Excel versions 2000 XP 2003 Consult factory for other versions 2 0 Description The PGA309DK key hardware consists of two boards see Figure 1 PGA309 Sensor Interface Board and PGA309 PC Inte
30. 3 This pop up window provides configuration control of the ADS1100 and the Port Expander PCF8574A jT PGA309 mes rd ADS1100 a d PCF85744A Stat O Muse nMieriace poar ar ALUS OutputV oltage Ref Set Hex ADC Contig Volt 0 5 Single Shot Someni Calibrate ADS1100 Read ADS1100 Continuously Interface Board and ADS1100 Supply NGC vs LT ADS Output Register Volt p D15 Di4 DIS Di Dil DIO D D D D DS D4 DS D DI D Dec lay He Mo t M H gagag anang e BEN MSB LSB Update V out Settings ADS1100 Configuration Status Register EVM PCF8574A Keep comm alive J PO Interface Test 4051110 Twvo Wire C OS DB pin nLED2 nLED1 Cal 23 2wWenwvSerlWen Jum UN DS SC Rl FO G1 c a fo fo fo fr fr fo fo ft fo fo o 1 o o 1 nameensm e 9 MSB LSB MB LSH E Gen Call Reset Update COM Port Checksums Setup EEPROM Lookup Table Bitmap of a register joard Communcation Idle Figure 23 ADS1100 and PCF8574A Status Window In the pop up window the bits under EVM PCF8574A will toggle when single clicked Table 6 describes the use of each of these bits If the Calibrate ADS1100 Button is pushed it will short the two inputs of the ADS1100 together and compute the offset error All ADS1100 readings which follow will be calibrated to account for this offset error In addition measure the voltage Vs on the PGA309 PC Interface Board with an accurate meter and enter this voltage in the Supply
31. 5 EX Pin 1 3 D3 L A m e Eh wg CQ E e N i eis Sai 6 LM p IN lo Jor A Co ho L L1 1 1 p l Rev A Boards Only Figure 4 PGA309 PC Interface Board Factory Jumper Settings PGA309 PC Interface Board Factory Jumper Settings Dynamic One Wire Pullup 1PU Enabled PC Serial Interface loopback set for CTS RTS Two Wire Enable Control by PC Rev A Boards Only Table 2 PGA309 PC Interface Board Factory Jumper Settings Rev 1 5 2 26 2004 8 46 00 AM Page 12 of 45 Preliminary 6 3 Hardware Setup see Figure 5 Plug the PGA309 Sensor Interface Board into the PGA309 PC Interface Board On the PGA309 PC Interface Board connect a eVdc 6Vdc 9Vdc Lab Supply into Tpwr or an AC Wall Adapter 120Vac RMS 60Hz in 6Vdc 200mA out USA Shipments Only into Jowr Connect the PGA309DK PC Cable from Ppc RJ 45 jack on the PGA309 PC Interface Board to an RS 232 serial port on the Test Computer AC Outlet 6Vdc Supply 6Vdc 9Vdc 200mA OR 120Vac RMS 60Hz N USA Only Lab Supply AC Wall Adapter IN 120Vac RMS 60Hz OUT 6Vdc 200mA PGA309 Designer s Kit pu ooftware PGA309 PGA309 ESS ZR Sensor Interface PC Interface A Board Board Test Computer Figure 5 Hardware Setup Initial Checkout 6 4 Board Control Software Installation 1 The PGA309Dk Board Control Software is installed in the normal Microsoft Windows manner Close all other applications From Start b
32. DC Configuration etc 2 The current configuration must be entered into the PGA309 Calibration spreadsheet To do this perform the following actions A Open the PGA309 Calibration Spreadsheet click Enable Marcos if asked Upon opening you will be asked if you would like to open the PGA309DK Board Control Program Answer Yes If you already have the software running a new window will not be open but a data link will be established B Make sure the current PGA309 register values are displayed in the Board Control Program click Read PGA309 button see Figure 32 7 Wribe E PSAs PGA Settings lanut Referred Off eet Inl Ta aaa Figure 32 Board Control Software Main Window Read PGA Button Write EEPROM C Return to the Main Worksheet and click Load Registers from Bench The register values in the cells B3 B12 will be updated The values of the gain offset and other parameters are set on the next worksheet accordingly to the PGA309 register configuration D Click Prepare Calibration Sheet The dialog box in Figure 33 will appear Select the appropriate algorithm The script will copy the right template to the Sensor Curvefit Worksheet and open the next page Rev 1 5 2 26 2004 8 46 00 AM Page 37 of 45 Preliminary PGA309 Calibration Please select the calibration algorithm One of the Following three templates can be used Far the pressure sensor calibration Cancel
33. E P ooo HOO O ooo0oo000000 ES 6006000000 v M OO0O0O0O0O0O0O00O000Oo0Oo0o0Oo0oooo 5o tn00 9999 eeeeeee oe 999 eeeeeee eeee ee eo eeeesee8 8 Xr E A 2 2 se eeeesee88 eeee68e8 eeeeee ee 9999 79 69999779799 eee t t 6999999959 9 9 9 NN tt 009000 oo0oo0o000009 o00000 o00000 oo0oo0o000 oooo0oc o Moo oM 000000000000000000000000 COMPLETE EVALUATION TOOL FOR PGA309 e PGA309 Hardware Designers Kit o Evaluate PGA309 User s Sensor o Full Temperature Evaluation e Software Control for Designer s Kit o Program PGA309 for Evaluation o Program PGA309 User s Sensor in Final Module o Computation Analysis Tool for Calibration of PGA309 Sensor Rev 1 5 2 26 2004 8 46 00 AM Page 1 of 45 Preliminary Table of Contents 1 0 PGA309DK Parts List 2 0 Description 3 0 PGA309 Sensor Interface Board Overview 4 0 PGA309 PC Interface Board Overview Part 1 5 0 PGA309 PC Interface Board Overview Part 2 PGA309 Sensor Interface Board Schematic PGA309 PC Interface Board Schematic Page 1 of 2 PGA309 PC Interface Board Schematic Page 2 of 2 6 0 Initial Setup and Checkout 7 0 Board Control Software Overview 8 0 PGA309 Sensor Calibration Spreadsheet for Microsoft Excel 9 0 General Operating Tips 10 0 PGA309DK PC Cable Drawing 11 0 PGA309DK External EEPROM Settings for Functional Test Note PGA309 Documentation Availability 5 6 6 7 10 11 21 2
34. EPROM Lookup Table Bitmap of a register Detecting PGA309 board Please stand by Figure 9 Software Startup Wrong Com Port Click on OK in the pop up window in Figure 9 Then click on COM Port Setup in the Main Window A new pop up window will appear as in Figure 10 Select the serial port where the board is connected and desired Baud Rate and click OK Ensure 1Wire Interface is selected 0000 0000 000000 Enable LIver LInder s cale Limits Overscale Limit oc Zire Tire show TkBi Figure 10 COM Port Pop up Window Rev 1 5 2 26 2004 8 46 00 AM Page 17 of 45 Preliminary Another pop up window will appear as shown in Figure 11 Click Yes and the two pop up windows should disappear with only the Main Window remaining as in Figure 8 al n Texas Instruments PGA309 Designer s Kit Control Program Edit L Reset Open File File Bench Setup AA E Write PGA309 Read PGA309 Write EEPROM Read EEPROM PGA Settings Input Referred Offset mJ9 000 Enable Internal Vref T Frontend PGA Gain V V 14 990 lt Vref Value 5 9 Rann Fault Detection m Detect External Faults 333 333m Save File Detect PRG pin shorted to Vout PGA3089 Test Pin HIGH M PGA309 Registers Click on the register to edit the value and see the details Binary Fine Zero DAC V ADC Out RO Fine Gain DAC Vv y Detect Internal Saturation ZeroDAC Gai
35. PGA309 Sensor Interface Board even when using Two Wire communication mode to the PGA309 and EEPROM from the PGA309DK Board Software See Section 7 8 for details 4 5 ADS1100 On Board A D Converter The ADS1100 is a 16 Bit A D available to measure Vout from the PGA309 The ADS1100 is configurable through the Board Control Software U4 provides a means of measuring the ADS1100 initial offset for improved accuracy in its readings 4 6 Test Points and Miscellaneous Breadboard Area There are several Test Points including a 3 position one for GND provided for ease of measuring analog signals Also provided are reserved areas with plated through standard spacing 0 1 holes for miscellaneous proof of concept breadboarding as desired for a given application 5 0 PGA309 PC Interface Board Overview Part 2 Refer to PGA309DK PC Interface Board Schematic Sheet 2 of 2 5 1 One Wire Active Pull Up The One Wire Active Pull Up circuitry is intended to provide a fast rising edge pull up when the One Wire interface is connected to heavy capacitive loads such as when PRG is tied to Vout on the PGA309 and there is a 10nF capacitor on Vout to GND In this configuration there is an extremely long rise time due to a 4 7kO pull up on the One Wire interface One Shot U14 is rising edge triggered only non retriggerable Comparator U12 looks for a rising edge to transition above 0 7V The One Shot U14 then triggers and produces a 5uS wide pulse which controls sw
36. Preliminar Burr Brown Products y PGA309DK from Texas Instruments User s Guide PGA309DK Designers Kit for PGA309 lt o 3 eeeeeeee X n 2752 201 1 1 1 Ex B s PGA309 PC I rface Boar d vO Hex mx 2 y nterface Board w R n22 beara 25 Burr Broun Products ED Ne ee RT C22 from Texas Instruments e eka e E31 po Gh U Burr Broun Products N T gt I from Texas Instruments 02 si mga ORE 2 a ge E akz 4503 4 2 Jm e ui 7 om dt NU 5 QI W Rigg ie 6 ee ee E Bad e LI E P P 7 23 211 3 2 M M LL 1 sev eee AB NE eee U LI E U 7 2 7 2S NI LO LEN NL Ll 32 8 32 11 EX 201 1121 ea ee ee 232211 11 e 99922 TJ eeeeeea 4s CG esec XIII K amp LU P 9 C eseeeeees 9 esee eee TTL eaeeeeeee ff H e H 9 T 99 111021131 aeeennee Fi eou C REF sod Fe Tio gr E3 Jtest i O50 aj L U idge m3 3 M c lt Test e fee paces q ET E d r g jj ia aooe it 3 3 m if min 1 eina Im fe fol m fen 71 ms m a Test ope aisle ae alio Big Bridge gt e lf L Jor A Ka AA M 47 E AT amr e EY a E e L nonem EE 3 5 5 M mm te Eee Pe ace 7e e oo oa a fes nee e jar AUT aj bad n nasus eeene eee eseveuees eee enews E SE s 1 E E 9 amp bk A a E C N 2 Ka Cy z i N oe SS ym E SE
37. S e Tes ee ee Y D1 T E te k HIHIH C9 1SMA5913BT3 AROSE F13 PRG DOINUDIMDNDBDIDBBDNBNBDBEIDNSM 0 1uF e Gay 82V ME she O AGND B EEEIEHIENMRHEDMEBAE ee i v ER am Vout C2 Ee e LE e peas O 8 C 0 01uF TOR b Vs int F103 Vexc C1 en e N e Tio 1 e ur l Pubs NN 0 01pF 300 e 9 REF Bridge Vs 4 er 10 3 16 bd a K Vcc Vso Vsa REF j i i 5 ee e 41 spa pur PRG 9 cea WP U2 13 ka Test e SCL 12 l kas 100pF SCL U1 PRG J8 T J10 5 PGA309 Vout 00 o ____ e i 7 a Short EU C3 Vind e ui Vour e e e R is R 4000pF 1kQ S 4 d J IN1 o Rt Bridge 9 c Vin2 e V 6 cL VoutF 4 Tin F1 e 0 01uF 1 Rp GN 0 01uF Vexc O o HE3 J3 1 o e 1000 150pF G S F3 Vin i C4 5 Vinz Vs 8 bd L RFO Vint Of o HEY Test 1000pF Vins O o HEP Ext bod T rso F3 5 Vin Bridge 15 9 e e J6 TEMP Test GND O o J11 aoe Temp O o cy et d E ONE GND 5 e N 2 11 GND O4 o i OR 1 Toa Be RGO EI Rt emp F7 Short C jre L l J12 a i 9 upw Em z e Rt eoo GND EIL Run Test Vs o o o b J7 R5 ANN m Sexy 10kQ 200 R1 10T R2 e 4 ko 1kQ Tin Bridge Connections Vexc Notes 1 All components must be rated for 40C to 125C Vbr 2 Jumpers shown with factory settings Vin PGA309DK Designer s Kit PGA309 Sensor Interface Board Schematic gt VIN Vbr Sheet 1 of 1 GND Rev 1 5 2 26 2004 8 46 00 AM Page 8 of 45 Preliminary
38. Select this when you do not know the 2nd order non linearities of output vs pressure and of temperature drifts of span and offset The module output must be measured at three different temperatures with min and Fulll scale pressure applied plus mid scale pressure at one of the temperatures 2 Temperatures and 3 Presures The 2nd order coefficients of temperature drifts of span and offset are known but Ehe non linearity of output vs pressure must be measured The module output must be measured at only Ewa temperatures with min and Fulll scale pressure applied plus the mid scale pressure at one of Ehe temperatures 2 Temperatures and 2 Presures All 2nd order coefficients are entered based on pre characterization anl the positions of curves must be Fitted The output must be measured at only two temperatures each with min and full scale pressure applied Figure 33 Select Calibration Algorithm Dialog E Verify and correct the parameter values in the light blue cells on the Sensor Curvefit Worksheet Figure 34 Fill out the highlighted cells PGA309 non variable during calibration settings Pressure values Initial settings of the Fain Adjust DACs Pmin Vref V GainDAC1 hex gt gt 0 6660 V V Pmax Kexc V V ZeroDAC1 hex gt gt 0 3160 V Gfront V V Alternative settings of Gain and ZeroDACs Temp range Gback V V GainDAC2 hex gt gt 0 3333 V V Tmin VosRti V ZeroDAC2 hex gt gt
39. The on board ADC ADS1100 on the PGA309 PC Interface Board requires two calibration steps for optimal accuracy The gain of the ADS1100 is set by its reference voltage which is the supply Vs Measure Vs on the PGA309 PC Interface Board test point TP Vs Ensure that the nVsens bit in the PCF8574A port expander is set to 0 See Figure 19 ADS1100 and PCF8574A Status and Control Pop up Window to turn Vs on Enter the measured value of Vs into the Supply Vcc V box under the Interface board and ADS1100 in the Main Window After this is complete go to the ADS1100 and PCF8574A Status pop up window See Figure 19 Click on Calibrate the ADS1100 This will measure the offset on the ADS1100 and the Board Control Software will adjust all future readings to account for the offset Rev 1 5 2 26 2004 8 46 00 AM Page 41 of 45 Preliminary 10 0 PGA309DK PC Cable Drawing BACKSHELL 1 CABLE 1 E S NC Grey Orange Lo Black OO QN Oe Green uy Yellow oes CON Brown L J CONNECTOR 1 DB9 Female Back side Solder Cup View 1 No Connection 2 RD 3 TD 4 DTR 5 GND 6 DSR 7 RTS 8 CTS 9 No Connection PGA309 EVM PC Cable Drawing THG January 16 2004 RJ45 Plug w Cable RJ45 Plug Cable Ridge Down CABLE 1 8 Conductor Modular Cable Grey COS Grey Orange E Orange Red mme Red Green emmm Gee Yellow Yellow Blue emm
40. adrant of the Main Window now displays detailed information about the PGA309 register selected by clicking on a specific register listed in the PGA309 Registers section of the Main Window Each bit in the selected register may be toggled by double clicking on the desired current bit setting A brief description of each bit also appears If the Instant Update check box in the lower right of the Main Window is not checked than the Write PGA309 button will need to be pushed Remember if you do not want the register settings in the PGA309 to be over written by valid PGA309 external EEPROM data then ensure the PGA309 Test pin is set high by checking the PGA309 Test Pin HIGH box in the upper left area of the Main Window Rev 1 5 2 26 2004 8 46 00 AM Page 25 of 45 File Edit Bench Setup R E m 33 m C Reset Open File Save File Deteck Write Pra 309 Read PGA309 PGA Settings input Referred Offset m 377m lt Frontend PGA Gain Cv A7 164 egg PRG pin shorted to Vout PGAS09 Test Pin HIGH f Click on the register to edit the value and see the details exa000 orat 0000 0006 Ox0001 D110 0001 noni Fine Zero DAC VY 1 00 000m 0999 990m Output Amp Gain s 7 2 400 Enable QyerUnder Scale Limits Ir Overscale Limit 3 976 LInderzcale Limit 247 808m Enable Sensor Excitation I Wexc 3 400 Linearization Coet v Pv 0 000 ADC Outro ZeroDAC GainDAc Ref amp Lin Gain v as Ctgl
41. alues of the all coarse settings must remain constant during the calibration processes The Lookup Table containing the values of the fine Zero and Gain DACs vs Temp ADC output is created during the calibration to produce the desired output signal at all temperatures We recommend to set both Zero and Gain DACs at mid scale each during calibration as this allows most adjustment range for calibration NOTE Set LinDAC 0 linearization disabled during calibration or a repeated re calibration Its value is also calculated during calibration Rev 1 5 2 26 2004 8 46 00 AM Page 33 of 45 Preliminary 8 3 Spreadsheet Overview The PGAS309DK Calibration Spreadsheet contains the following parts 1 The Main Worksheet is shown in Figure 28 It contains the current values of the PGA309 register table the lookup table and the control buttons The buttons have the following functions A Load Registers From File Read register values from a text file saved by PGA309DK Board Control Program B Load Registers From Bench Read configuration register values directly from the PGA309DK Board Control Program must be currently running Using A or B will update the gain offset and reference values used for calibration C Prepare Calibration Sheet Prepare the Worksheet Sensor Curvefit for calibration using one of the three templates described in Section 8 1 and start entering calibration measurements D Save Registers Lookup Table A
42. ate Vout Button 5 Repeat Step 4 for measuring the max scale and if needed mid scale Vout values in the cells E26 E27 6 Place the Sensor PGA309 at the temperature Tmeas2 and repeat the Steps 3 4 5 entering the values to the corresponding cells below the ones shown in Figure 36 At each stage make sure the signal path of the PGA309 is not overloaded by reading the state of the Alarm Register 7 If using the 2 Temperature 3 Pressures or 2 Temperature 2 Pressures algorithms enter the second order parameter non linearities of the sensor in the highlighted cells B33 B36 8 Verify that the resulting fitted sensor approximation Figure 30 are in agreement with the characterization data 9 Go to the next Worksheet Calibration Results and enter the desired output voltage scale in the cells B4 B5 the number of the Lookup Table points in the cell E4 and the temperature range where the calibrated output signal is expected in cells E6 E7 see Figure 38 Note that this can be a narrower range than the Tmin Tmax range used for the sensor curve fitting Using a smaller temp range will reduce the spacing between the points on the piece wise linear PWL gain and offset curves generated by PGA309 This in turn will reduce the residual 3 order errors of the output The resulting lookup table and the simulated plot at the bottom of the page get instantly updated The plot axes might have to be adjusted to display the curves
43. c will become the Vs for the PGA309 Sensor Interface Board For further ADS1100 details consult the ADS1100 data sheet Rev 1 5 2 26 2004 8 46 00 AM Page 28 of 45 Preliminary Logic Description Comments State P7 PGA309 operates in Normal Stand Reads external EEPROM and uses Test pin Alone Mode temperature coefficients to update Gain DAC and Zero DAC settings 1 PGA309 operates in Test Mode No external EEPROM reads and must be manually written to for changes in DACs or register settings Turns on LED D2 on PGAS309 PC LED D2 is turned on by the Board Control Interface Board Software if PGA309 Test Pin HIGH box in the Main Window is checked 1 Turns off LED D2 on PGA309 PC LED D2 is turned off by the Board Control Interface Board Software if PGA309 Test Pin HIGH box in the Main Window is not checked LED D1 is turned on by the Board Control Software when successful communication has nLED2 U o Turns on LED D1 on PGA309 PC Interface Board been completed after power on from zero volts on the PC Interface Board mg J 1 Turns off LED D1 on PGA309 PC Interface Board Normal ADS1100inputoperation ff ADS1100 1 Shorts ADS1100 inputs Vn and Vin Used in the ADS1100 calibration sequence by Cal together for offset calibration the Board Control Program Logic output of port expander port P3 Spare port expander port available for user 1 PGA309 PC Interface Board U5 application if de
44. data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties conditions limitations and notices Reproduction of this information with alteration is an unfair and deceptive business practice Tl is not responsible or liable for such altered documentation Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice Tl is not responsible or liable for any such statements Mailing Address Texas Instruments Post Office Box 655303 Dallas Texas 75265 Copyright O 2004 Texas Instruments Incorporated Rev 1 5 2 26 2004 8 46 00 AM Page 45 of 45
45. djustment DAC MSB LSB value for TO and below 1 23 22 TEND MSB LSB end of Look up Table 0 25 24 ZME MSB LSB End of Look up Table 0 FFFF sum Hex Eq of each location 27 26 17 16 thru 24 23 truncated above 16 MSB LSB bits Checksum2 1 Rev 1 5 2 26 2004 8 46 00 AM D13 GO1 0 CLK CFG1 ADC2X D13 Location 1 1 8 4 MSB D12 D11 D10 1 0 1 0 0 0 0 0 0 SD EXS EXEN 0 0 1 GOO GI3 GI2 1 0 1 CLK CFGO EXTEN INTEN 0 1 0 ADCS ISEN CEN 0 0 1 0 0 0 Location 1 1 8 4 D12 D11 D10 0 1 0 0 0 1 1 1 1 1 1 1 0 0 0 0 0 0 Page 43 of 45 D9 RS Gl1 EXTPOL 1 TEN D9 Location 0 4 2 1 8 LSB D6 D5 D4 D3 1 0 0 1 0 0 0 0 0 0 0 0 LD6 LD5 LD4 LD3 LD2 LD1 0 0 0 0 0 0 OS4 OS3 OS2 OS1 0 0 1 0 OUEN HL2 HL1 HLO LL2 LL1 1 0 0 0 RVO M1 MO G1 0 0 0 0 1 1 0 1 Location 0 4 2 1 8 D6 D5 DA D3 0 0 0 0 1 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 1 0 1 Hex Eq 5449 0000 0000 0500 1611 0A47 0603 7FA4 805B Hex Eq 0800 0640 FFFF 7FFF 0000 18E3E 71C1 Preliminary PGA309DK IMPORTANT NOTICE Texas Instruments Tl provides the enclosed product s under the following conditions This evaluation kit being sold by TI is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not considered by TI to be fit for commercial use As such the goods being provided may not be complete in terms of required design marketing and or manufacturin
46. e Vs i t y ry 11 18 Qd TF M UT3 O O O 110 0 0 O 5 0 0 0 0 i RINS po E p eui l i l 9 E s s s s s s s s s l E S 1 V 1 DIN5 Miscellaneous Breadboard Area e PC Master ku DOUTS G dm A qM MER MN NM E Serial Connection on 16 c Data Out gt R13 D mors Data In lt 10ko JF SDN Rev A _ Boards Only n Note 7 13 15 rose PGA309DK Designers Kit 1 All Data Signal Directions are relative to _FORCEON 7 INVAL PGA309 PC Interface Board Schematic PC Master FORCEOFF Sheet 1 of 2 2 Jumpers shown with factory settings Hev 1 5 2 26 2004 8 46 00 AM Page 9 of 45 Preliminary R18 4 TkO D4 MMBD4148 d Vs Je VV 1206 R19 4 7kQ SN74LVC1G66 DS MMBD4148 LMv331 SOT23 5 D6 Vs MMBD4148 AF TPU E AVV 4 Bus typ C24 SN74LVC1G66 220pF R24 18 2kQ 9 RT SN74LV221A TSSOP 16 One Wire Speedup PGA309DK Designer s Kit PGA309 PC Interface Board Schematic Sheet 2 of 2 Hev 1 5 2 26 2004 8 46 00 AM Page 10 of 45 Preliminary 6 0 Initial Setup and Checkout 6 1 PGA309 Sensor Interface Board Factory Jumper Settings Confirm and or set the jumpers on the PGAS309 Sensor Interface Board as shown in Figure 3 The desired j
47. e the number of required measurements to 2 temperature points with 2 pressure levels at each 2 temperature 2 pressure calibration In cases when the pressure non linearity is not known due to bridge resistor value mismatch or other reasons three pressure levels need to be measured at one of these temperatures 2 temperature 3 pressure calibration The PGA309 Calibration Spreadsheet includes templates for each of the three methods described above The exact equations for curve fitting the sensor are not included in this document but can be extracted from the spreadsheet cell formulas Rev 1 5 2 26 2004 8 46 00 AM Page 32 of 45 Preliminary 8 2 Calibration of Signal Path Errors Since we are interested in calibrating the output of a full module Sensor PGA309 we can measure the output of the PGA309 Then we curve fit the result to the same model This will take into account all offsets gain errors and drifts of the amplification signal path PGA309 and sensor must be pre configured with desired settings reference excitation level coarse gain offset A D configuration etc The coarse settings should be based on preliminary characterization of the sensor and be such that the PGA309 produces a reasonable valid output signal range say within 2096 of the target at both zero and full scale pressure level without saturating the internal signal path Since the circuit offsets can be different at different gains and offset levels the v
48. egister bit values to zero Open File Selects File to open which contains saved EEPROM Configuration Register and Lookup Table values Save File Selects File to save current EEPROM Configuration Register and Lookup Table values Looks for PGA309DK Boards using current Port Setup Configures the board and read the current Register and the Lookup Table values Writes all current Main Window values into PGA309 R W Registers including setting ZeroDAC and GainDAC Detect Write PGA309 Head PGA309 Write EEPROM Writes current values in the Lookup Table section and PGA309 Register section of the Main Window into external PGA309 EEPROM Read EEPROM Table 5 Main Window Top Row Control Buttons _ UM Reads all current PGA309 Register values into the Main Window Reads external PGA309 EEPROM values into Main Window Resets values in PC memory only Requires a Write to PGA or Write to EEPROM to effect Description Comments See Related Figure Figure 18 Both PGA309 Sensor Interface and PGA309 PC Interface must be present and working Unless Test Pin is set high these settings will be overwritten by valid external EEPROM data 7 1 1 General Note on Reading amp Writing to PGA309 and External EEPROM When you do a Write EEPROM whatever is in the Main Window will be written to the PGA309 external EEPROM EXCEPT for the Zero DAC and Gain DAC values in the PGA Settings section
49. fter the calibration has been completed you have to return to this Worksheet and save the resulting configuration register values and the Lookup Table to a text file The file can be later read by the PGAS309 Board Control Program and written into EEPROM on the PGA309 Sensor Interface Board Fd Microsoft Excel PGA309_Calibration xls E ES rm x Bs File Edit view Insert Format Tools Data Window Help Acrobat x D a B a ela 4 Bam cc O08 x amp 5 20 M A iv 012 rm reqval2str calechecksum C6 C9 D amp h5449 D 0 A B C D E B IL 5 H PGA309 Calibrated Lookup Table Position Temp ZIM GM 1 PGA309 Configuration Registers 2 Reg Addr Mame Binary value Dn ADC OutfRO pana 0000 0000 0000 1 feroDAc pana nang 0000 0000 2 GainDAc pana 0000 0000 0000 3 Ref amp Lin OO00 0000 0000 0000 4 Gain vos Cfg oodo 0000 0000 0000 5 Cfg2 Overlander 0000 0000 0000 0000 b Cfga3 ADC pana 0000 0000 0000 7 QutEnbl Counter O000_0000 0000 0000 B8 Alarmstatus RO O000 0000 annon UU Config Checksum 1010 1011 1011 0110 E Load Registers from File 18 19 Load Registers From Bench 2 Prepare Calibration Sheet 24 25 save Registers Lookup Table coo O ee to KD Sa C Jh EN nn ld 4 K Hs Main J Sensor Curvefit Calibration Results Template2T_3P Tem k 3 Ready Figure 28 Main Worksheet Rev 1 5 2 26 2004 8 46 00 AM Page 34 of 45 Preliminary
50. g related protective considerations including product safety measures typically found in the end product incorporating the goods As a prototype this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may not meet the technical requirements of the directive Should this evaluation kit not meet the specifications indicated in the PGA309DK User s Manual the kit may be returned within 30 days from the date of delivery for a full refund THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES EXPRESSED IMPLIED OR STATUTORY INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE The user assumes all responsibility and liability for proper and safe handling of the goods Further the user indemnifies TI from all claims arising from the handling or use of the goods Please be aware that the products received may not be regulatory compliant or agency certified FCC UL CE etc Due to the open construction of the product it is the user s responsibility to take any and all appropriate precautions with regard to electrostatic discharge EXCEPT TO THE EXTENT OF THE INDEMNITY SET FORTH ABOVE NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES TI currently deals with a variety of customers for products and therefore our arrangement with the user is
51. high O Force VOUT lowe UEN Cer Inder Scale Limit Enable 1 Enable 0 Dizable L 2 0 Over Scale Threshold Select L z n Under Scale Threshold Select PS Interface Two Vyire C Keep comm alive Instant Update H ne E Autocalc Chksum w Eu Update COM Port Checksums Setup EEPROM Lookup Table 0404 Cfg2 0verUnder Board Communcation Idle Figure 21 PGA309 Registers Main Window 7 4 PGA Settings Rather than toggling individual bits of the registers described above the PGA309 can be configured using drop down menu selections or check boxes in the PGA Settings section of the Main Window contains Input Referred Offset mV Frontend PGA Gain V V Fine Zero DAC V Fine Gain DAC V V Output Amplifier V V Enable Over Under Scale Limits Overscale Limit Underscale Limit Enable Sensor Excitation Linearization Coef V V Enable Internal Vref Vref Value Changing these settings will update the corresponding bits of in the register table and vice versa The current values of these and the PGA309 registers will be automatically updated in the Main Window following a Read PGA309 The current settings displayed in the Main Window will be written to the PGA309 internal registers following a Write PGA309 or to the external PGA309 EEPROM following a Write EEPROM If the Instant Update check box in the lower right of the Main Window is checked then the PGA309 internal registers will automatica
52. in nLED2 nLED1 Cal 3 Z2WwenavSer1Wven HJ o o o 1 m ES H Y o o gj 0 g 1 erface Board and ADS1100 MSB LSB MSB LSB Supply Vee V 5 0 Vot 4 91318 Hex BENI Update Vout Settings PGA Interface Two Wire C tad 14 Keep comm alive Instant Update T One ire Show 1kBit Autocalc Chksum V 7 EEPROM Update COM Port Checksums Setup EEPROM Lookup Table Bitmap of a register Board Communcation Idle Figure 15 Status Window Rev 1 5 2 26 2004 8 46 00 AM Page 20 of 45 Preliminary 5 In the Status Window check the box to Read ADS1100 Continuously 6 In the Main Window set Supply Vcc V to 5 0V 7 The Rtest potentiometer and J4 on the PGA309 Sensor Interface Board will be used for this test On the PGA309 PC Interface Board the ADS1100 ADC will be used for this test Table 4 below details the actions and acceptable results for a pass condition of the PGA309 Sensor Interface and PGA309 PC Interface Boards Yee mE mm o m9 max until audible clicking is heard Rotate Fully Bad Counter Clockwise until audible clicking is heard a Replace J4 Table 4 Hardware Checkout Voltages and Settings 8 In the Main Window under PGA309 Temp ADC click on Convert see Figure 16 9 Temperature reading in C should be the PGA309 ambient 2 C Readout will be in Main Window under PGA309 Temp ADC section as shown in Figure 16 PGA 302 Temp ADC Deg
53. itch U13 When switch U13 is turned on a 2000 pull up to Vs is provided on the One Wire Interface At the end of the 5uS pulse the 2000 pull up to Vs is removed The 5uS was chosen to provide a near symmetrical rise and fall time into a 10nF load on the One Wire interface RT is a provisional potentiometer which can be added to change the time the active pull up is applied to the One Wire Interface D5 D6 and R22 proved a clamp to keep the input of U12 inside its allowed input voltage range for reliable operation Figure 2 illustrates the One Wire Pull Up into a non capacitive load The table shows typical values for a supply voltage of 3 0V Rev 1 5 2 26 2004 8 46 00 AM Page 6 of 45 Preliminary Tek SGT Single Seq 10MS s F Chi RMS 2 115V SIBI 500mV Currant Saver Fartorv save wim Recall Wim Format Typical 2 63V Figure 2 One Wire Active Pull Up Waveform and Typical Levels Vs 3V 5 2 Vs Quick Discharge It is desired at times to cycle the power on the PGA309 to be able to communicate through PRG when it is tied to Vout while Vout is set to high impedance by the PGA309 on initial power up The supply voltage on the PGA309 must decay to near zero to ensure that on power up the state of the PGA309 is set correctly With a 10uF capacitor on Vs on the PGA309 PC Interface Board and another 10uF capacitor on Vs on the PGA309 Sensor Interface Board reliable reset operation is guaranteed by discharging these capacitors thr
54. late used This calculates a GainDAC correction factor in the cell 186 Return the Gain DAC to its original value Please note when using these correction factors the resulting plot on the Calibration Results worksheet will appear off target Initial Settings Tip Use the coarse offset adjustment on the PGA309 to maximize the adjustment range for the Zero DAC refer to the Offset Scaling Section of the PGAS309 User s Guide 8 4 Customization of the PGA309DK Calibration Spreadsheet All of the cells as well as the VBA code in the spreadsheet are open and can be modified and adjusted for individual design and sensor properties The name of the custom sensor curve fitting function is sensbridge This function can be modified to fit sensors modeled by more complex equations than shown in Equation1 In this case the following parts of the spreadsheet must also be updated curve fitting coefficient equations in the framed area A17 152 worksheet Sensor Curvefit references to the sensbridge in the cell equations in the worksheet Sensor Data vs Temp columns D F kK L references to the sensbridge in the cell equations in the worksheet Sensor Data vs Pressure column B Note The equations generating the Lookup Table in the worksheet Calibration Results can stay Rev 1 5 2 26 2004 8 46 00 AM Page 40 of 45 Preliminary 9 0 General Operating Tips 1 During initial evaluation of the PGA309 Sensor it is recommended to leave the PRG pin
55. lly be updated after every change Remember if you do not want the register settings in the PGA309 to be over written by valid PGA309 external EEPROM data then ensure the PGA309 Test pin is set high by checking the PGA309 Test Pin HIGH box in the upper left area of the Main Window Rev 1 5 2 26 2004 8 46 00 AM Page 26 of 45 Preliminary 7 5 Fault Detection In the Fault Detection section of the Main Window the following check boxes are provided for fault detection configuration Detect External Faults checked means enable detection of external faults Detect Internal Faults checked means enable detection o internal faults Vout high on external fault unchecked means Vout low on external fault Vout high on internal fault unchecked means Vout low on internal fault The current settings of these in the PGA309 registers will be automatically updated in the Main Window following a Read PGA309 The current settings displayed in the Main Window will be written to the PGA309 internal registers following a Write PGA309 or to the external PGA309 EEPROM following a Write EEPROM If the Instant Update check box in the lower right of the Main Window is checked then the PGA309 internal registers will automatically be updated Remember if you do not want the register settings in the PGA309 to be over written by valid PGA309 external EEPROM data then ensure the PGA309 Test pin is set high by checking the PGA309 Test Pin HIGH box
56. lt 4 Temperature ADC Configuratio m TE Move your mouse cursor over the choices to see corresponding register bits Select Signal Source External TEMPin pin C Apply Cancel Continuous conv WV Internal on chip temp f Resolution incl sign 10b 11b 12b 13b e Single Shot conv v Enable Itemp ZuE T ADC Configuration with External Source Enable ADC 2x Turbo 7 ADC Pre gain Select PVN e ADC input ZY C gain AVAL C BYA C Ref select ADC built in 2 048 T Vref pin Vexc pir C Vsapin C Reserved C Note Bits Rv 1 0 do not have effect when the built in Vref is selected Diff input TEMPin GNDa gt Vexc TEMPin C Vout GNDA C Vref TEMPin C Yout GNDA input is not compatible with the stand alone look up table PGA309 mode Pull Test pin high Figure 22 PGA309 Temp ADC Configuration amp Readback Rev 1 5 14 EKI YOUL high on internal fault PGA309 Temp ADC DegC 29 375 degC Hex Interface Board and ADS1100 Supply Vcc v 5 0 vot 404093 Hex 6772 ENN Settings Update Vout PGA Interface Keep comm alive T Convert Two L Instant Update T aia de Autocalc Chksum v One Wire e Update COM Port Checksums Setup 2 26 2004 8 46 00 AM Preliminary 7 7 Interface Board and ADS1100 In the Interface Board and ADS1 100 section in the Main Window click on Board Settings A pop up window will appear as in Figure 2
57. n initial software startup a Main Window will appear with a smaller pop up window in the middle of the Main Window Click Yes on the pop up window see Figure 7 If the initial software startup does not look like Figure 7 then proceed directly to Section 6 5 3 Sec E c ay ule e e Reset Open File Save File Detect Write PGASO9 Read PSASO9 Write EEPROM Read EEPROM i PGA Settings E PRG pin shorted to Vout PGA309 Test Pin HIGH T Input Referred Offset m 1a agg Enable Internal rek T Frontend PGA Gain V7 4 agg Tm Vref Value 5 0 z Fault Detecti mrm Fine ero DAL VT 0 000 Eyes rae Addr Mame Binary Detect External Faults p000 ADC Out RO 00030 0000 0000 DOC E Fine Gain DAC V v E 333 333m Detect Internal Saturation 0001 eroDAC 0000 C0000 0000 0000 DOE Output Amp Gain V V nes mm Vout high on external fault 0010 GainDAC DxDODD axo nona 0000 007 a Wout high on internal fault Enable D ver Lnder Scale Limits E 0011 Ref amp Lin 0x0000 o lt 0000 nono 0000 00C Sues Eri v FGA309 Temp ADC 0100 Gain vos Cigi 0000 xunun 0000 0000 007 285 Dead 0101 Cfg OverUnder Ox0000 ox0000_0000_0000_o00C Underscale Limit 497 000m Dec psd 0110 cigs ADC 0x0000 00000 nono nono aoc DNI IMMUNE B 0144 OutEnbl Counter ADC Config 1000 AlarmStatustRO bB PGA309 Designer s Kit 28 convert Camia aeret wn The Interface Board appears to be connected
58. nDAc Ref amp Lin Gain Vos Cfq1 0x0000_0000_0000_0000 0x0000_0000_0000_0000 O0x0000_0000 0000 0000 ox0000_0000_0000_0000 O0x0000 0000 0000 0000 Output Amp Gain V v 2 000 X Enable Over Under Scale Limits B Overscale Limit da ge Vout high on external fault Vout high on internal fault PGA309 Temp ADC nce Convert erface Board and ADS1100 5 0 Board Update Vout Settings PGA Interface Two AMire C Cfg2 OverUnder Cfg3 ADC OutEnbl Counter AlarmStatus RO Config Checksum i COM Port Setup Ox0000_0 Select Serial Port PGA309 Designer s Kit E3 m Interface a Hex The Interface Board appears to be connected Do you want to load the EEPROM and register contents into the PC memory 9 e Lookup Table TFFF 0000 8000 upply vec Ny Keep comm alive Instant Update T One AMire Autocale Chksum Iv Update COM Port Checksums Setup EEPROM Lookup Table Bitmap of a register Figure 11 Communication Pop up Window after COM Port Setup 6 5 4 Hardware Checkout 1 In the Main Window click on Open File A pop up window will appear as in Figure 12 PGA309DK Test txt Read Me txt File name PGA309DK Test Ivt Y Text txt Y Open as read only My Network Places Cancel Files of type ER Figure 12 Open File Pop up Window Rev
59. not exclusive Tl assumes no liability for applications assistance customer product design software performance or infringement of patents or services described herein Please read the PGA309DK User s Manual and PGA309 Data Sheet and specifically the Warnings and Restrictions notices in the Manual and Data Sheet prior to handling the product This notice contains important safety information about temperatures and voltages For further safety concerns please contact the TI application engineer Persons handling the product must have electronics training and observe good laboratory practice standards No license is granted under any patent right or other intellectual property right of Tl covering or relating to any machine process or combination in which such TI products or services might be or are used Mailing Address Texas Instruments Post Office Box 655303 Dallas Texas 75265 Copyright O 2004 Texas Instruments Incorporated Rev 1 5 2 26 2004 8 46 00 AM Page 44 of 45 Preliminary IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries Tl reserve the right to make corrections modifications enhancements improvements and other changes to its products and services at any time and to discontinue any product or service without notice Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete All products are sold subject to TTS
60. of the Main Window However in the case of the Zero DAC and the Gain DAC it does not make any sense to write to the EEPROM the settings in the section PGA Settings since the Zero DAC and Gain DAC settings can be many values as defined by the Lookup section of the EEPROM To write Zero DAC and Gain DAC settings into EEPROM you must update or change the Lookup Table section in the Main Window Also if you type a number into the Zero DAC or Gain DAC boxes in the PGA Settings section of the Main Window and then do a EEPROM Read the previously typed numbers will remain To read the current Gain DAC and Zero DAC settings of the PGA309 internal registers and have them updated and displayed in the PGA Settings section of the Main Window click on the Read PGA309 Button If you want to try different settings on the PGA309 then it is best to check the box PGA309 Test Pin High in the upper middle area of the Main Window which stops the PGA309 from reading the EEPROM and allows you to Write PGA309 which will directly change but NOT save to EEPROM the Zero DAC and Gain DAC settings for trial offset and gain settings etc Rev 1 5 2 26 2004 8 46 00 AM Page 23 of 45 Preliminary Look in 2 PGA3DSDK CD Rev 1 0 6 amp ter EE x E PGAZ09DK Test txt File name PGASUSDK Test i My Network Files of type Test tet
61. ough U15 and R25 Whenever Q1 see Sheet 1 of 2 PGA309 PC Interface Board Schematic is off and disconnects power from Vs then U15 is on for quick discharge of Vs And whenever Q1 is on then U15 is off Rev 1 5 2 26 2004 8 46 00 AM Page 7 of 45 Preliminary F8 j y F9 gt Vs T GND REF e SCL Hd O O O O t 0 O O O i1 0 O O O SDA SDA S Vs O e SCL ee ae PN LI Bs PR A u nu amp 2 NH 0c a c F11 GND o emer nema
62. properly Pay attention to the Result Sanity Check messages in the cells B11 B13 If the required DAC or ADC values are outside of the linear ranges of the PGA309 the message will inform you about it This means that the coarse parameters of the PGA309 must be adjusted and the calibration has to be repeated Rev 1 5 2 26 2004 8 46 00 AM Page 39 of 45 Preliminary PGA309 Desired output and its look up table Lookup Table Parameters Resulting Look up Table Look up table Hex Enter Output Scale 3t of points Point Temp Gfine V V GainSlope Vzero V ZeroSlope Temp ZM Vout_max V Ntemp 417 50 0 703735 0 286542 F808 11E9 Vout_min V Optional 37 5 0 706215 0 000198 0 29596 0 000753 FB32 002F LUT Tmin degC LUT Tmax degC 0 709357 0 000251 0 303348 0 000591 FE5C 0026 0 713177 0 000306 0 308706 0 000429 0185 001B 0 717697 0 000362 0 312034 0 000266 04AF 0011 0 722944 0 00042 0 313332 0 000104 07D9 0006 0 728947 0 00048 0 3126 5 85E 05 0B02 FFFD 0 735743 0 000544 0 309839 OE2C FFF2 0 743374 0 00061 0 305048 0 000383 1156 FFE8 0 751888 0 000681 0 298227 0 000546 1480 FFDE 0 76134 0 000756 0 289376 0 000708 17A9 FFD3 0 771795 0 000836 0 278495 0 00087 1AD3 FFC9 0 783326 0 000922 0 265584 0 001033 1DFD FFBF 5 0 796016 0 001015 0 250644 0 001195 2126 FFB4 0 809964 0 001116 0 233674 0 001358 2450 FFAA 0 82528 0 001225 0 214673 0 00152 277A FFAO 0 842093 0 001345 0 193643 0 001682 2AA3 FF95 0 842093 0 0 193643 o
63. rature drift ridge This is the sensor model used in the PGA309 Calibration Spreadsheet There are three degrees of freedom in this equation offset and span vs temperature and sensitivity vs pressure each of them is described with a quadratic equation If we don t know much about the sensor besides that it can be approximated with the Equation1 we need to measure three points on each degree of freedom for curve fitting i e 9 measurements zero and full scale output at 3 temperatures each for offset and span and output at 3 pressure level for sensitivity Since the min and max pressure levels for the sensitivity can be combined with zero and span measurements this reduces the total number to 7 measurements zero half full scale at one of the temperatures zero and full scale at each of two other temperatures This is called the 3 temperature 3 pressure calibration Since over temperature calibration in an oven is often a lengthy and expensive process it is often preferred to characterize the span and offset drift non linearities on some number of sensor samples and avoid using the 3 temperature test in production In this case if we know that the sensor exhibits for example 9 span drift non linearity over the full temperature range and we measure only two points on this curve we can find the equation coefficients The same is true for offset drift and pressure non linearity By using this pre characterization method we can reduc
64. rface Board The PGA309 Sensor Interface Board contains the PGA309 external SOT23 5 EEPROM and several jumpers for ease of bridge sensor configuration The PGA309 PC Interface Board contains an RS 232 serial interface a 3V 5V programmable linear regulator a switch for power control to the PGA309 Sensor Interface Board both One Wire and Two Wire interface configuration and control logic and an A D Converter ADS1100 The PGAS309DK is designed to allow the user to attach his sensor to the PGA309 Sensor Interface Board and place this combination in a temperature chamber By controlling the applied pressure to the pressure sensor and the temperature of the temperature chamber the PGA309 Sensor combination can be calibrated for optimum end module accuracy The PGA309 Sensor Interface Board is rated for operation from 40 C to 125 C Power ground output and digital interface wires connect the PGA309 Sensor Interface Board in the temperature chamber to the external PGA309 PC Interface Board The PGA309 PC Interface Board communicates to a test computer through a standard RS 232 serial port via the PGA309DK PC Cable For USA shipments an AC wall adapter is included to provide 6Vdc to the PGA309 PC Interface Board For all other applications an alternate connection on the PGA309 PC Interface Board is provided for connection to a eVdc 6Vdc 9Vdc lab supply The on board A D Converter ADS1100 on the PGA309 PC Interface Board allows for easy reading of
65. rnal EEPROM Pop up Window Rev 1 5 2 26 2004 8 46 00 AM Page 24 of 45 Preliminary E Dis Dia ois ore pri oro ps ps D7 ps os TRT o2 bi oo rae NT 57 pe ps os ps p Tp po oo GEET a Dis pi ors pepu po pops Figure 20 PGA309 Internal Registers to PGA309 External EEPROM Mapping For updating the information in the EEPROM Lookup Table section simple click and edit the desired values Next click on the Apply Changes button in the EEPROM Lookup Table section This only updates the information for the Lookup Table information stored on the Test PC If these new values are desired to be written into the external EEPROM then after the Apply Changes click one must click on the Write EEPROM button at the top of the Main Window If the changes edited in the Lookup Table are desired not to be kept on the Test PC then click on Discard Changes and the last values in the Lookup Table stored on the Test PC will be restored The other way to directly write to the external EEPROM is through the PGA309 External EEPROM Pop up Window as shown in Figure 19 and discussed above 7 3 PGA309 Registers The PGA309 current internal register contents are displayed in the PGA309 Registers section of the Main Window By clicking on the Bitmap of a register tab in the bottom left corner of the Main Window the Main Window view will change to that of Figure 21 The lower left qu
66. rnal temperature sensing using an RTD or external diode is to be used then set J6 to EXT and remove the J1 jumper entirely to avoid any interaction with Rt or Rt J9 provides hardware configuration for either internal or external reference voltage J8 is used when Vout is to be tied to PRG for a 3 terminal sensor module configuration J12 and J7 together decide if the Test pin on the PGA309 is to be controlled by the PGA309 PC Interface Board or hardware programmed on the PGA309 Sensor Interface Board 3 3 PGA309 External SOT23 5 EEPROM U1 is the PGA309 for evaluation Also on board is a 16k bit external SOT23 5 industry standard Two Wire EEPROM U2 Although the PGA309 needs only 1k bit of external EEPROM to access its configuration registers plus the maximum number of 17 temperature coefficients both the One Wire and Two Wire interfaces allow access to locations in much larger EEPROMs which can be used to store user specific information such as a serial number lot and date code information etc Rev 1 5 2 26 2004 8 46 00 AM Page 4 of 45 Preliminary 3 4 Protection and Filtering The PGA309 Sensor Interface Board is configured with components to prevent mis wire mishaps If power is provided from the PGAS309 PC Interface Board D1 is adequate to protect from overvoltages and reverse polarity connections CL is a standard EMI RFI capacitor design with Riso and Rp providing up to 16V overvoltage on VoutF Input common mode plus differential noi
67. se filtering is provided by C3 C4 C5 and R3 R4 3 5 Test Points and Miscellaneous Breadboard Area There are several Test Points including a 3 position one for GND provided for ease of measuring analog signals Also provided are reserved areas with plated through standard spacing 0 1 holes for miscellaneous proof of concept breadboarding as desired for a given application 4 0 PGA309 PC Interface Board Overview Part 1 Refer to PGA309 PC Interface Board Schematic Sheet 1 of 2 4 1 Input Output The connections from the PGA309 PC Interface Board to the PGA309 Sensor Interface Board are provided through Tio an 8 position screw terminal strip This connector provides ease of connections to wires for the required selected signals when placing the PGA309 Sensor Interface Board inside a temperature chamber for PGA309 Sensor calibration In parallel with Tio is Ptest which provides a means for direct plug in connection to the PGA309 Sensor Interface Board This is useful for initial checkout of the PGA309DK system Ppc is an 8 position RJ45 jack for connection through the PGA309DK PC cable to a test computer s RS 232 serial port RS 232 compatible signals are generated through U9 Power for the PGA309 PC Interface Board is provided through either Jpwr or Tpwr Jpwr is to be used when an AC Wall Adapter 120Vac RMS 60Hz in 6Vdc 200mA out is available USA Shipments Only Other applications will use a 6Vdc 6Vdc 9Vdc lab supply and the
68. sired pin 7 Disables the Two Wire interface from To allow reliable uninterrupted connection to the PGA309 Sensor Interface Board ADS1100 and PCF8574A when PGA3098 is in Stand Alone Mode set this bit to zero 1 S P4 NO u m N Z Enables the Two Wire interface from To allow for Two Wire digital communication the PGA309 Sensor Interface Board from PC to PGA309 and external EEPROM Applies Vs to PGA309 Sensor Important when PRG is connected to Vout on Interface Board PGA309 to ensure One Wire communication during power up P1 nVSen 1 Hemoves Vs from PGA309 Sensor Important when PRG is connected to Vout on Interface Board PGA309 to ensure One Wire communication during power up PO Important to disable for unloaded PGA309 1Wen resistor Vout accurate reading through ADS1 100 FEN resistor Table 6 Functionality of Port Expander PCF8574A Bits default initial values selected by the Board Control Software are highlighted in bold Rev 1 5 2 26 2004 8 46 00 AM Page 29 of 45 Preliminary 7 8 Interface The Interface section in the Main Window allows for selection of One Wire or Two Wire digital communication with the PGA309 Sensor Interface Board Refer to Figure 24 A single click in the respective circle will select the desired interface All Board Control Software functionality is supported over either of these interfaces however the One Wire interface is the preferred one due to potential conflicts arising from two
69. sistive pull up for the One Wire interface is enabled or disabled through U1 The One Wire pull up can be disabled for an accurate PGA309 Vout reading without the extra loading due to R3 JC provides a selection for the One Wire active pull up 1PU or no One Wire active pull up 1NPU This feature is described in detail in Section 5 1 Jumper JB provides a mechanism for communication through Vout when PRG is tied to Vout on the PGA309 for a 3 terminal sensor module configuration Rev 1 5 2 26 2004 8 46 00 AM Page 5 of 45 Preliminary 4 4 Two Wire Digital Interface Two Wire digital interface is provided through the conversion of RS 232 signals from U9 into open drain outputs with pull ups SDAoy through U6 and SCLour through U8 SDAyqy is tied direct to U9 which is looking for 0 8V for a logic low and gt 2 0V 3V supply or gt 2 4V 5V supply for a logic high U10 and U11 provide a mechanism through software or hardware JE to separate the Two Wire bus interface from the PGA309 if it is physically connected If the PGA309 is in stand alone mode it will be routinely accessing its external EEPROM via the Two Wire interface as a master By disconnecting from the PGA309 Two Wire connections dedicated local Two Wire transactions on the PGA309 PC Interface Board such as reading the ADS1100 U3 can be conducted reliably and without interruption Note It is recommended to keep One Wire interface on the PGA309 PC Interface Board connected to the
70. t Amp Gain X24 0 0 0 ZeroDAC 100mV 0 O C E ae 3 976V ideal 000 0 9708 Vref Under Scale 0 248V ideal 111 0 06054 Vref ee OO Fault Detect EXTEN 1 Enable External Fault Comparator Group PY INTEN 0 Disable Internal Fault Comparator Group Po QUENZ I Enable Over Under Scale Limits Table 3 PGA309DK Sensor Interface Board Functional Test Settings 3 Write these settings to the PGA309 Sensor Interface Board EEPROM by clicking on Write EEPROM in the Main Window Click on Read EEPROM and then click on Read PGA309 The Main Window should look the same as in Figure 14 4 Configure ADS1100 for continuous readback In the Main Window click on Board Settings The Status Window ADS1100 and PCF8574A Status Window will appear as in Figure 15 i Texas Instruments PGA309 Designer s Kit Control Program Res OutputV oltage Ref Set PRG pi able Internal Vref v PGA30 ke ag mchana Calibrate ADS1100 sf Vale 4096 cick on Hex 7DC7 ault Detection Read ADS1100 s Read ADS1100 Gen Call Reset Detect External Faults Daci Continuously Detect Internal Saturation out high on external fault ADS Output Register out high on internal fault D15 D14 D13 D12 Dit D10 DS ODE D7 D6 DS D4 D3 p p1 Do A309 Temp ADC ofr fr fr fr fr fo fr fe fe fo fo mpg p aem ia 98h ADC Config ADS1100 Configuration Status Register EVM PCF8574A Convert Test ADS1110 OS DE Dy SG Rd p
71. the analog output of the PGA309 The PGASO9DK Software is comprised of two parts The Board Control Software contains all of the interface and control for communication to the PGA309 through the PGA309 PC Interface Board It allows for reading and writing to all registers in the PGA309 as well as reading and writing to the external SOT23 5 EEPROM Both Two Wire and One Wire communication options are available In addition configuration of the PGA309 PC Interface Board and readback of the ADS1100 is provided The PGA309 Calibration Spreadsheet for Microsoft Excel provides a useful tool to calculate optimum temperature coefficients for the PGA309 Sensor calibration based on real world measurements of pressures at different temperatures The PGA309 Calibration Spreadsheet also contains Visual Basic for Applications code that allows its integration with the Board Control Software These macros allow the user to exchange PGA309 settings between the program and the spreadsheet and save the resulting EEPROM configuration file Rev 1 5 2 26 2004 8 46 00 AM Page 3 of 45 Preliminary Power Supply Customer Sensor ix RS232 PRG Vn e ul m PGA309 T GND 10nF L SDA 3 SCL Two Wire EEPROM PGA309 PC Interface Board PGA309 Sensor Interface Board Temperature P d Chamber
72. then the first screen will look like Figure 9 i Texas Instruments PGA309 Designer s Kit Control Program h Setup Z R 53 ur C e Reset Open File Save File Detect Write PGA309 Read PGA309 Write EEPROM Read EEPROM PRG pin shorted to Vout B PGA309 Test Pin HIGH C verear EET GERA Md iind Input Referred Offset mV gg v Enable internal Vref 7 Frontend PGA Gain V V 4 990 v Vref Value 9 0 Fault Detection Bie Zetia EIN Detect External Faults ADC Out RO 0x0000_0000_0000_0000 Fine Gain DAC V V 333 333m Detect Internal Saturation ZeroDAC Ox0000 0x0000_0000_0000_0000 i Output Amp Gain V V 3000 Vout high on external fault GainDAC Ox0000_0000_0000_o0000 Vout high on internal fault Ref amp Lin 0x0000_0000_0000_0000 Enable Over Under Scale Limits PGA309 Temp ADC Gain VOS Cfq1 O0x0000_0000_0000_0000 Overscale Limit TT j Deg c E Cfg2 OverUnder Ox0000_0000_0000_o000 Udanan 1777 Cfg3 ADC 0x0000 0000 0000 D000 creat Ben OE CoU 0x0000 0000 0050 7000 Enable Sensor Excitation Hex Ane Config AlarmStatus RO _ 0x0000 Err 0 Config Checksum 0x1010 EM Convert interface Board and ADS1100 8000 Hex UNE Update Vout Settings PGA Interface TwoAMire C Keep comm alive Instant Update M One Vvire 9 Show 1kBit Autocalc Chksum Iv EEPROM Update COM Port Checksums Setup E
73. ting Equations Generation of Values for the PGA309 Temperature Lookup Table and Internal Register Settings The spreadsheet also contains VBA Visual Basic for Applications code that allows its integration with the Board Control Software These macros allow the user to exchange PGA309 settings between the program and the spreadsheet and save the resulting EEPROM configuration file The flexibility and wide availability of Excel determined the platform for this solution You are free to customize the sensor curve fit model to fit your sensor better The only prerequisites are familiarity with Microsoft Excel capabilities and some limited knowledge of Visual Basic for Applications 8 1 Sensor Curve Fitting Equations The built in equations approximate the sensor with second order polynomials for each of the sensor three variables Span vs temperature Zero offset vs temperature Output signal vs sensor input variable it will be simply called pressure from now on but can also be flow or another measured physical parameter The sensor curve fit equation for this case is Equation K p T k k T k T ps k pl ek Tk where Kpriage bridge output function in V V of excitation p sensor input variable pressure etc T temperature in degrees C ko k1 k2 offset polynomial coefficients initial first and second order drift k3 k input variable sensitivity and non linearity Ke ke span first and second order tempe
74. turns to Board Communication Idle before pushing any button Repeated pushing of buttons when the Board Software is in the middle of communication with the PGA309 will cause unreliable data transfer and nuisance errors 5 The most quiet analog readings with a voltmeter or oscilloscope on Vout of the PGA309 are accomplished when there is no digital activity from the test PC to the PGA309 PC Interface Board and the PGA309 Two Wire Bus is isolated from the PGA309 PC Interface Board The RS 232 interface chip U9 MAX3238 on the PGA309 PC Interface Board has a shutdown feature which disables the on board positive and negative charge pumps These capacitive charge pumps are noisy and every attempt has been made on the PC Interface board to filter them away from the Vs for the PGA309 However some amount of noise does still exist and as such does not give a true indication of the PGA309 noise performance on its output Vout After 30 seconds of inactivity on U9 the internal charge pumps are shutdown Easiest check that U9 is in shutdown is to probe TP V for a voltage reading of lt 0 1Vdc To ensure U9 goes into shutdown cease all communications to the PC Interface Board through the RS 232 Interface Ppc and ensure that the Two Wire interface is disabled form the Sensor Interface Board through either software or hardware program selection of disable on U10 and U11 Once U9 is shutdown a quiet reading on Vout of the PGA309 can be taken 6
75. umper settings are also described in Table 1 PGA3OS Sensor Interface Board uu Burr Broun Products from Texas Instruments Rev A e e e e GND REF ane J5 Uexc e e e ej Us S REF CL O Jtest L F2 Uinl i C Test DES R3 O nin F3 R mn J3 C ef T jy C SL Test LI re xi CB B CJI Bu i Test FO Rtest J2 if e Bridge MA 1 F 1 1 Fl ds i J wj s ajm m Vs 10 Bridge i dt short Us IHI lee _ LR Vexc L TEMP Figure 3 PGA309 Sensor Interface Board Factory Jumper Settings PGA309 Sensor Interface Board Factory Jumper Settings Use on board pot for bridge Use on board pot for bridge Use on board pot for bridge Use PGA309 Vexc Use on board pot for bridge Use on chip temp sensor Use EEPROM for settings PRG not connected to VOUT Internal Reference Use on board pot for bridge Use on board pot for bridge PC Interface Board control for Test Mode Rev 1 5 2 26 2004 8 46 00 AM Page 11 of 45 Preliminary Table 1 PGA309 Sensor Interface Board Factory Jumper Settings 6 2 PGA309 PC Interface Board Factory Jumper Settings Confirm and or set the jumpers on the PGA309 PC Interface Board as shown in Figure 4 The desired jumper settings are also described in Table 2 PGR309 PC Interface ou b R22 C ES E R24 aT 22 LI L Gaal Burr Broun Products DS griel C C24 E Vcc from Texas Instruments L J on Ww QJ ia c NE pl ox Tpur Us L TN gt Bf 4 LI aia 0 1 130
76. utton on the task bar select Run 2 In the Run Window type d setup where d is the letter designation of the CD ROM drive containing the PGA309DK Software CD ROM 3 Follow the on screen prompts to install the software 4 To remove the PGA309DK application use the Windows Control Panel utility Add Remove Software 6 5 Software Hardware Initial Checkout At this point no LEDs should be lit on the PGA309 PC Interface Board If any LEDs are lit cycle the power on the PGA309 PC Interface Board Rev 1 5 2 26 2004 8 46 00 AM Page 13 of 45 6 5 1 Software Startup Start the PGA309DK Board Control Software by clicking on PGA309 DK Board Interface under the Start menu All Programs PGA309 Designers Kit as shown in Figure 6 Recycle Bin Character fo x H Internet Shortcut Explorer vspic i i Ro Ss X Cy y E ZEA 3 Windows Explorer Hummingbird Modem He Neighborhood Tow AY a0867024 Wi MSN Explorer gt MSN Explorer C3 Windows Explore E Launch Microsoft Shortcut to Visio exe Shortcut to EYCEL 67 Shortcut to WINWOF e Acrobat Reader 5 1 M Notepad Texas Instruments E x iPassConnect y Paint 8 Shortcut to vspice e PN PGA3OSEVM Test Prd All Programs S Ur J start T DESKTOP INI NetMeeting New Office Document dd Open Office Document E PeoplePC Online Set Program Access and Defaults W windows Catalog A Windows Update Y3 Yahoo

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