VXI LOAD OPERATIONS MODELS 81201 & 81210 USER`S MANUAL
Contents
1. DATA 20 and Hex F7 or Hex 40 write to device address 20 DATA 20 DATA 20 DATA 20 and Hex BF write to device address 20 DATA 20 ran nee 17 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 18 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 5 READING AND METERING 5 1 Reading Load Status Executing a read from device address 20 will return a value for load status Only the 5 LSB are defined BO EEPROM DO Data line to read when reading EEPROM data B1 Short relay on off A high indicates that the short relay has been activated B2 Normal Power limit A low indicates the load is in power limit B3 ADC status converting Done A high indicates the ACD converter is running B4 Overtemp Normal A high indicates an overtemp condition 5 2 Reading the Analog to Digital Converter ADC The following shows the type of algorithm required to control the ICL7109 ADC 1 Select the load function to be read 2 Set run hold line high a DATA 20 DATA 20 or Hex 10 write to device address 20 DATA 20 3 Delay 10mS at least 4 Set run hold line low a DATA 20 DATA 20 or Hex EF write to device address 20 DATA 20 5 Monitor the ADC status line until it goes low a Read device address 20 b If data read and Hex 08 8 then keep reading this until it equals zero 0 6 Read data a Read device address 24 to get 8 LSB b Read device address 26 to get 4 MSB c Ifthe data read fro2. HEX OF 4 LSB DATA 22 DATA 22 and HEX OF or LSB 16 save the DATA 22 register write to device address 22 DATA 22 write to device address 26 MSB DEE EE aI N 15 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 4 4 Set the Load Operating Mode This function will set constant current or constant resistance operation CONSTANT CURRENT DATA 28 DATA 28 and Hex FC save value of register 28 write to device address 28 Hex FC clear mode DATA 28 DATA 28 or 1 Constant Current Mode write to device address 28 DATA 28 write to address CC Mode CONSTANT RESISTANCE Same as above only Constant Resistance Mode is a 2 DATA 28 DATA 28 or 2 Notes e A nominal voltage value should already have written prior to setting CR mode e The data written to address 28 should always have DO or D1 set e To read load voltage or operate in constant resistance mode the sense inputs must be connected SET THE LOAD SLEW RATES There are 3 possible slew rate values Slow Hex 8 Medium Hex 4 Fast Hex 0C Define rate appropriate Hex value DATA 28 DATA 28 and Hex F3 clear slew registers DATA 28 DATA 28 or RATE set desired rate write to device address 28 DATA 28 4 5 Miscellaneous Functions SHORT THE LOAD DATA 20 DATA 20 or 8 write to device address 20 DATA 20 16 of 27 ran aak VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL UNSHORT THE LOAD OR RESET OVER VOLTAGE LATCH
3. 5 2 READING THE ANALOG TO DIGITAL CONVERTER ADDO esse ees ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee 19 3 3 METERING usa oras OE ON EE OE AE EE EE OR OE AE STA 20 6 CALIBRA TION ee Ee oe dika RN 21 APPENDIX A GER EE cuccessecsecdesseacaaec K e S WE AO SAN EVOR VE SA 23 SPECIFICATIONS AND PANEL CONNECTIONS x ee ee esse ee se ee ee ee ee ee ee ee ee ee ee K ee ee KK KK KA KK ee 23 APPENDIX B OE EE EE ii inici 27 EEPROM TIMING DIAGRAM S venceran RS 5e3 GE es 27 MEE NE seur nee 5 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 6 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 1 INTRODUCTION VXIbus electronic loads are designed for low power output loading of DC power supplies or other devices needing loads with either static or dynamic modes of operation Each load is a self contained instrument on a single slot C size VXlbus module making them ideal for applications where size is important The 81201 and 81210 can be integrated into any VXlbus based test system but they are particularly well suited to the POWERTEST family of automatic power supply test systems from NH Research Although rated at 50 Watts continuous power the 81201 and 81210 can be used at considerably higher ratings As most testing is carried out at substantially lower duty cycles analog control circuitry is used to continuously monitor internal conditions permitting the load to in
4. 1 address 0 Word 2 IADC gain address 1 Word 3 IADC offset address 2 Word 4 VADC gain address 3 Word 5 VADC offset address 4 Word 6 IDAC gain address 5 Word 7 IDAC offset address 6 Data is read by setting EEPROM Chip Select CS high then serially shifting the address data into the EEPROM via EEPROM Data Input DI and EEPROM Serial Clock SK The operation code for read is 110 followed by a 6 bit address value in the form A5 A4 A3 A2 Al AO The 16 bit data value for the desired address is then read from the EEPROM Data Out DO line in the format 0 D15 D14 D2 D1 DO Note that the first bit read is always 0 and should be discarded All input output data is valid on the low to high transition of EEPROM SK For example to read the IDAC gain This example we would like to read word 7 or address 6 of the EEPROM From the device dependent register list we see that EEPROM Chip Select CS is Bit 0 or BO Also EEPROM Serial Clock SK is Bl and EEPROM Data Input DI is B2 All of these are at Base Address Offset 20 ran nee 13 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL B2 B1 BO Write to address 20 data lt 1 0 0 1 an instruction pending Write to address 20 data 3 O 1 1 clock in pending instruction Write to address 20 data 5 1 0 1 clock low first bit of read op code 110 Write to address 20 data lt 7 1 1 1 clock in read command Write to address 20 data 5 1 0 1 clock low second b
5. 1 good O bad ADC STATUS 1 Converting O done OVER TEMPERATURE 0 ADC Lower 8 bits ADC Upper 4 bits ADC Overrange ADC Polarity EEPROM CHIP SELECT EEPROM SERIAL CLOCK EEPROM DATA INPUT SHORT CIRCUIT ON ADC RUN OV RESET also clears short circuit Current DAC LSB s Voltage Scaling DAC LSB s Current DAC MSB s also loads LSB s Voltage Scaling DAC MSB s loads LSB s Current and Voltage Mode Control 10 Constant Resistance 01 Constant Current Slew Rate Control 10 slow 01 medium 11 high not used Current Metering Voltage Metering Temperature Metering aran VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 3 1 General Programming Structure Typical operation of a load is described below This assumes the resource manager RM of the system has recognized the Load The load supports VXI MODID device recognition 1 Configure A Read EEPROM data to determine the calibration data offset and gain factors for the various functions B Save this data in memory 2 Reset load to desired start conditions A Registers for addresses 20 22 and 28 should be saved They will be referred to as DATA 20 DATA 22 and DATA 28 These variables will contain the last data written to these addresses 3 2 Reading The EEPROM Calibration data is stored in a the EEPROM serially Following is a description of each of the calibration words All values are signed integers Word 1 EEPROM data valid
6. 5 decimal would look like 12345678 X X XXX X open closed X X The remaining addresses listed are OFFSET values from the base address Also addresses are HEX values unless specified explicitly There are four 4 types of VXI load registers that begin at this Base address A11 addresses are 16 bits REGISTER OFFSET ID read 00 DEV TYPE read 02 STATUS read 04 write BIT DEFINITION BO B11 Manufacture ID B12 B13 00 address space A16 24 B14 B15 11 register based BO B11 Model Code B12 B15 1110 required memory B2 1 self test passed B3 1 self test extended B14 MODID self test extended B15 A24 active BO Reset B1 Sysfail Inhibit other bits not used B15 A24 Enable All device dependent registers begin at address 20 HEX There are 5 device write registers and 3 device read registers rennet 11 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL READ ADDRESSES _ OFFSET Load Byte 20 Over Load Byte 24 Load Byte 26 WRITE ADDRESSES OFFSET Load Byte 20 Load Byte 22 Load Byte 24 Load Byte 26 also all Analog Switches 28 12 of 27 BIT DEFINITION BO Bl B2 B3 B4 B5 B7 BO B7 BO B3 B4 B5 BIT DEFINITION BO Bl B2 B3 B4 B5 B6 B7 BO B3 B4 B7 BO B7 BO B7 BO Bl B2 B3 B4 B5 B6 B7 EEPROM DATA IN OUT SERIAL SHORT CIRCUTT also after an Voltage Power Limit
7. VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL rN EE aI Part No 09 0129 REVISION C March 31 1998 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL Document History Rev C ECO 14612 3 31 98 2 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL Proprietary Rights Notice This document and the information that it contains are the property of NH Research Incorporated The rights to duplicate or otherwise copy this document the rights to disclose the document and its information to others and the right to use the information therein may be acquired only by written permission signed by a duly authorized officer of NH Research Incorporated Unauthorized duplication of software and documentation provided with the test workstations violates the copyright protection provided by law However backup copies of programs are permitted for archives and recovery from hardware failures The material in this publication is current as of the release date on the cover page and is subject to change without notice Any questions concerning the product or any questions or comments concerning this manual should be directed to the NH Research Field Service Department during normal business hours Monday through Friday at 949 474 3900 or FAX 949 474 7062 or www nhresearch com POWERTEST and POWERFLEX are trademarks of NH Research Incorporated ran nee 3 of 27 VXI LOAD OPERATIONS MODELS 81201 am
8. arptr 1 14 of 27 ran nae VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 4 OPERATING COMMANDS 4 1 Load Reset To reset the load the following steps must be taken 1 Set the load current to zero 0 2 Set the load mode to constant current 3 Turn off the meter bus 4 Pulse the over voltage reset line 4 2 Set Load Current This function sets the current drawn by the load and requires two writes to the load Assume AMPS is the current to be set To calculate what bits to write to the load scaling must be done Multiply the desired current by the IDAC gain previously extracted from the EEPROM Add the IDAC offset Divide by the full scale current 81201 1 Amp and 81210 10 Amps and multiply by 4095 Scaled AMPS AMPS IDAC gain IDAC offset Bits to write Scaled AMPS full scale current 4095 Calculate the most significant bits MSB MSB Bits to write 16 integer divide to get 8 MSBs LSB Bits to write and HEX OF get 4 LSBs DATA 22 DATA 22 and HEJOFO or LSB save the DATA 22 register write to device address 22 DATA 22 write to device address 24 MSB 4 3 Set the Load Voltage This command sets the nominal load voltage used for constant resistance mode This function requires two 2 writes Assume VOLTS is the nominal load voltage to be set Bits to write VOLTS 75 4095 scaled by full scale voltage MSB Bits to write 16 integer divide to get 8 MSB LSB Bits to write and
9. crease its power handling capability with decreasing duty cycles Because the monitoring is carried out in real time the protection circuitry is tripped only if the load is in danger of being damaged This allows testing for short periods or small duty cycles at power levels in excess of the steady state specifications If higher power is continuously required two or more loads may be operated in parallel The 81201 and 81210 offer programmable transient response Programmable rise times permit the dynamic characteristics of the load to more closely approximate the operational conditions in which the unit under test UUT will be expected to function In applications requiring testing under complex loading profiles an analog input is provided which allows external control of the load current over the load s full operating ranges Using an arbitrary waveform generator virtually any required loading profile can be realized Frequently switching power supplies must be turned on into a constant resistance load before testing with a constant current load can begin The 81201 and 81210 provide a glitch free transition from one mode to another the supply under test does not see the load current fall to zero during the mode transition In the short circuit mode of operation an SCR in parallel with the shorting relay is used to give fast low resistance short It is possible to shift from any mode to any other mode of operation under program control The l
10. diagram Appendix B 22 of 27 FETTER VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL APPENDIX A SPECIFICATIONS AND PANEL CONNECTIONS VDC Current Range Range Power BW 1 5 75 VDC 1A 50 W 100 KHz 1 5 75 VDC 10A 50 W 100 KHz Note All VXIbus loads will operate below 1 5 volts in the constant resistance mode The programmed load voltage must still be within the ranges specified above Current Programming Accuracy 0 4 of FS 0 4 of setting Resolution 12 bits 1 Amp full scale 0 26 milliAmps 10 Amps full scale 0 52 milliAmps Voltage reading Resolution 12 Bits Accuracy 0 1 of FS 40 5 of reading Current reading Resolution 12 Bits Accuracy 0 2 of FS 40 4 of reading Operating Modes Constant Resistance Constant Current Short circuit on off Shut down high Z Equivalent Resistance Accuracy 2 V I Load Speed 10 to 90 risetime SW selectable FAST MEDIUM SLOW 5 uSecs 50 uSecs 500 uSecs ran nee 23 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL VXIbus Load Module Front Panel Logical Address JI Auxillary J2 UUT Input J3 Over voltage power supply JA Over voltage coil 24 of 27 ran nae VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL VXIbus Load Module Front Panel o 2 Pin 2 ol Pin J3 9 2 Pin 2 o 1 Pin y N a Pin Pin Pin Pin Pin Pin PNW AU A o o o o o o H J3 co
11. ge is scaled for any nominal operating voltage selected by DAC U19 Voltage references of both DAC U19 Constant Resistance and DAC U18 Constant Current can be controlled by op amp U1 This method of controlling the reference allows the current of the load to be proportional to the UUT voltage i e constant resistance mode Analog switch U16 controls the selection of references and the mode of operation Constant Resistance or Constant Current U16 also controls slew rates by selecting between RC timing networks 2 1 Protection Temperature is sensed on the load heat sink by a temperature transducer The output is scaled by op amp U15 and is compared to a stabilized reference The output of the transducer is also scaled by op amp U8 and summed along with power multiplier U7 Both outputs of the op amps are ORed through diodes CR8 and CR9 If power is exceeded or the temperature should rise above the preset value the load will be shut down and a status bit will be available to the controller ran nee 9 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 10 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 3 VXI LOAD PROGRAMMING SPECIFICATIONS In general all addresses are offset values from the base load logical address as set be the DIP switch SW1 SW1 open 1 closed 0 ADDRESS NUMBER 1 OU BORN A7 A6 AS A4 A3 A2 Al AO For example the logical address switch setting for 2
12. it of read op code 110 Write to address 20 data 7 1 1 clock in second bit of read op code Write to address 20 data 1 O 0 1 clock low last bit of read op code 110 Write to address 20 data lt 3 O 1 1 clock in last bit of read op code The EEPROM now needs the Address Address6 000110 For each 0 write 1 followed by 3 For each 1 write 5 followed by 7 Now that the command and address have been set reading address 20 should have BO and B1 both O zero This is the data start bit and should be discarded For each bit of data Write a 1 followed by a 3 clock low to high and then read the data bit on the EEPROM Data Output DO line This must be done 16 times in order to read the entire 16 bit value Please see timing diagram in appendix B Offset and Gain are divided by 10000 decimal to convert from integer to floating point values Set Current offset IDAC OFFSET 10000 Set Current gain IDAC GAIN 10000 Read Current Offset IADC OFFSET 10000 Read Current Gain IADC GAIN 10000 Read Voltage Offset VADC OFFSET 10000 Read Voltage Gain VADC GAIN 10000 Note Some offset factors may be large i e in the 65000 range These are actually small negative number because the MSB sign bit implies an negative value The EEPROM should only be read once The gain and offset factors saved in memory for later usage These numbers must be stored in standard 8088 16 bit Integer format with the 8 LSB at Varptr 0 and 8 MSB at V
13. m address has bit 4 set indicates and ADC overrange data read and Hex 10 d If data read and Hex 20 0 then signal is negative 7 Scale data depending on function being read and set proper polarity for reading For Voltage If DATA and Hex 20 0 then the voltage is negative For Current If DATA and Hex 20 Hex 20 then the current is negative There really is no such thing as a negative current for this load so this value should be returned as O amps ran nee 19 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 5 3 Metering The load has both current and voltage available as measured values READ LOAD CURRENT To select current readings DATA 28 DATA 28 and Hex OF or Hex BO write to address 28 DATA 28 Once selected read the ADC to get LSB the 8 least significant bits MSB the 4 MSB To scale reading Bits MSB 256 LSB Store full scale current 3839 0 Bits Current Reading IADC gain Store IADC offset READ LOAD VOLTAGE To select voltage readings DATA 28 DATA 28 and Hex OF or Hex BO write to address 28 DATA 28 Once selected read the ADC to get LSB the 8 least significant bits MSB the 4 MSB To scale reading Bits MSB 256 LSB Store 0 0195 Bits 0 0195 79 8525 4096 Voltage Reading VADC gain Store VADC offset 20 of 27 ran nae VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 6 CALIBRATION All the Calibration data i
14. nnector type NHR part Pin 1 J1 Pin 2 Pin 3 Sl o o Pin 4 o o Pin 5 o o Pin 6 o o Pin 7 1j o o Pin 8 Pin 9 ae Notes OV Coil relay OV Coil relay NHR part 6300052 OVPS input OVPS input input input input input input input ro 1 6300830 input voltage input voltage NC Current Monitor NC Current Monitor NC J4 connector type MOLEX 09 50 3021 NHR part 6300052 drive drive MOLEX 09 50 3021 J2 connector type MOLEX 09 50 3061 NHR part 6300074 J1 connector type AMP 87922 1 sense sense Ret External Modulation NC External Modulation Ret Current Monitor is an output analog voltage from O to 8 VDC which corresponds to a current from 0 to ES External Modulation is an analog input voltage ranging from 0 to 10 Volts with load set to O amps The voltage sense MUST be connected in order to enable voltage readback 25 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 26 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL APPENDIX B EEPROM TIMING DIAGRAMS REAO O XOX HIGH 2 di uy o C Co ly WRITE EWEN ETE Nm EN ON JER VN ENABLE 11 DISABLE 00 ran nee 27 of 27
15. oads are fully protected against various fault conditions including overvoltage reverse voltage overcurrent overpower and overtemperature All calibration and configuration data is stored in an on board EEPROM resulting in fast internal no pots calibration of setting and metering parameters The result is a rugged highly reliable load that requires minimal maintenance ran nee 7 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 8 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL 2 OPERATIONAL THEORY The VXlbus loads use power MOSFETs for the current sinking devices The control circuits are practically identical for both the 81201 and the 81210 loads A few resistors and a capacitor in the feedback are the differences see page 3 of drawing 10 3860 A control voltage is routed to the inverting input of an op amp U9 The voltage developed across the precision shunt is scaled and routed back into the op amp This op amp drives the gate of the MOSFET and will slew controlling the current until the error goes to zero The control voltage is programmed by the use of a 12 bit DAC U18 The stable voltage reference for the DAC comes from U13 The DAC reference can come from 2 places one is the fixed reference the other is derived from the constant resistance DAC U19 The UUT voltage sensed by op amp U1 is scaled such that full scale voltage represents 3 75 VDC This voltage representing the UUT volta
16. p 81210 USER S MANUAL 4 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL TABLE OF CONTENTS 1 INTRODUCTION EE EE N ER ER EE sa San RE SE SEA AA KONAN OK 7 2 OPERATIONAL THEORY eossse sesse oes see de ee ede gede 5 Dee ee ebes n sd gie ee 000 6 ee bu ke gee w 0 ede see do dee 9 2 A PROTECTION EA OO OE EE A a EE N 9 3 VXI LOAD PROGRAMMING SPECIFICATIONS ee essssssssssss ss ss ss se se se cooooos 11 3 1 GENERAL PROGRAMMING STRUCTURE cccssecccessecscsceeeccsececcusecsceucecsseueccecsseuseseueecsseueesessuecsseeuesees 13 3 2 READING THE EEPROM 0 cccccsccccceseccccececceceeccccueccccseecsceueessueccssueccesseccssueccssuueccesaeeceesaeceees 13 4 OPERATING COMMANDS ccccssscsssccccccsscscscscccccceccssscscccccceeccsscsscccceeeccscssccccceecescsscccceeseesecscees 15 Ap MIELOAD RESET ds 15 4 2 SET LOAD CURRENT US EER A Esa 15 43 SET THE LOAD VOLTAGE lt lt c se Me ee pias lamas Der ERA ee kene na ee e ee Bee We Eg een er 15 44 SET THE LOAD OPERATING MODE ie es Ee ae Se acosa 16 AS MISCELLANEOUS FUNCTIONS smiriti karke set ee ve ee ee ee ee aa bn ee a see ee We eke Ee ee wa ke Ge kura yk ka De De a 16 5 READING AND METERING sssssssssssssssesssesezenn nau baw uw uw Gee Gee w w H H H HA HA HA HA HA HA HA HA HHHH HHHH HH HH HHHH HHH HK 19 5 1 READING LOAD STATUS si yiy e 5ye M Gees es ee ee dE sk iia e d Si 19
17. s stored on the EEPROM internal to the unit This allows for a software no pots calibration Calibration data is stored in a the EEPROM serially Following is a description of each of the calibration words All values are signed integers Word 1 EEPROM data valid 1 address 0 Word 2 IADC gain address 1 Word 3 IADC offset address 2 Word 4 VADC gain address 3 Word 5 VADC offset address 4 Word6 IDAC gain address 5 Word 7 IDAC offset address 6 A precision shunt a DC Supply and a DMM are needed to calibrate the load Calibration points are 10 and 90 of Full Scale Voltage and Current Calibration Equations are as follows Gain QC2 X1 Y2 Y1 Offset Y2 X1 Y1 X2 Y2 Y1 IDAC X1 10 OF FULL SCALE CURRENT 1 AMP for model 81201 and 10 Amps for model 81210 X2 90 OF FULL SCALE CURRENT Y1 READING OF SHUNT AT 10 SETTING Y2 READING OF SHUNT AT 90 SETTING IADC XI READING OF SHUNT AT 10 SETTING X2 READING OF SHUNT AT 90 SETTING Y1 READING OF IADC AT 10 SETTING Y2 READING OF IADC AT 90 SETTING VADC X1 VOLTAGE READ AT 10 SETTING DMM X2 VOLTAGE READ AT 90 SETTING DMM Y1 VOLTAGE READ AT 10 SETTING VADC Y2 VOLTAGE READ AT 90 SETTING VADC Calibration parameters should be multiplied by 10000 decimal to convert floating point to integer value before writing to the EEPROM The registers in the EEPROM must be erased all bits set to logical 1 before new data can be written into the registers Regis
18. ters are erased by setting the EEPROM Chip Select CS high then serially shifting the operation code and address data into the EEPROM via EEPROM DI and EEPROM SK please refer to section 3 2 Reading the EEPROM ran nee 21 of 27 VXI LOAD OPERATIONS MODELS 81201 amp 81210 USER S MANUAL The operation code for read is 111 followed by a 6 bit address value in the form A5 Ad A3 A2 Al AO After the Erase instruction is loaded into the EEPROM CS must be pulled low The falling edge of this signal initiates the self timed programming cycle If CS is brought high after a minimum delay of lus the DO pin will remain low as long as the EEPROM is still in the programming mode and the return of this signal to logical 1 indicates the device is now ready for the next instruction After erasing the register write the new calibration parameters Data is written by setting the EEPROM Chip Select CS high then serially shifting the operation code and address data into the EEPROM via EEPROM Dl and EEPROM SK please refer to section 3 2 Reading the EEPROM The operating code for a write is 101 The 16 bits of data must be loaded into the device in the format D15 D14 D2 D1 DO After the last bit of data is loaded CS must be brought low before the next rising edge of the serial clock The high to low transition of CS will initiate a programming cycle to the register whose address was specified in the write instruction Please refer to timing
Download Pdf Manuals
Related Search