PGA309: PGA309 Multi-Cal Communication Error

just tried using the Iout Pre-cal file for the voltage output unit and was able to successfully communicate.  This unit is definitely a voltage unit as it was giving a 0-5VDC output prior to these communication issues...

Is something wrong with this hardware?

Hoping someone can help soon!

Hello Avi,

Most common questions and issues related to the PGA309 interface communication are frequently related to the PRG One-Wire interface settings. The PGA309 PRG interface register settings need to be set properly to support either 3-wire or 4-wire voltage output modules or current output modules.  Depending on the One-Wire interface settings, there may be a time interval restriction to establish communication to the PGA309 One-Wire interface. The Multi-Cal system only uses the PRG One-wire interface to communicate with the PGA309 or the EEPROM (the I2C 2-wire EEPROM interface is not directly accessible) 

For example, on "three-wire" voltage output modules, the PRG is connected to the Vout pin, and the PGA309 PRG interface communication can only be accessed for a few milliseconds after power up, after this delay, the interface becomes inactive, and communication is no longer accessible and the amplifier Vout is active. Therefore, when using the device with OWD set to ‘1’ (Register 4, bit D15, One-wire Disable), the time interval after power-up is the only opportunity that an external communications controller can initiate digital communication with the PGA309 and trigger a one second delay in the internal state machine. After VOUT is enabled, no further digital communication is possible, unless power is cycled.

I will attempt to reproduce the issue on the Multi-Cal system.

Please provide the following information:

1) Is the OWD (Register 4, bit D15, One-wire Disable) set to '1' on your application? 

2) Please share the Pre-Cal file and/or model file of the 4-20mA Current Sensor.

3) Please share the schematic of the Current-Output 4-20mA PGA309 test card showing the DSUB-9 connector to the muti-cal interface card connection.  If this is a PGA309 test card with selectable jumpers, please show the jumper positions on the PGA309 board test card.  If you are connecting the PGA309 sensor board to the Multi-Cal Interface board using the screw terminal block, please show a diagram of the terminal block sensor to Muti-Cal Interface connections.

4) If the issue is also occurring on the voltage output sensor, please clarify if this is a 4-wire or 3-wire voltage output sensor.  Please share the Pre-Cal file and/or model file of this voltage output sensor.

5) Please also share the schematic of the voltage-output PGA309 test card showing the connections to the PGA309 Multi-Cal interface board. If you are connecting using the screw terminal block, please show a diagram of the terminal block to Muti-Cal Interface connections.

I will get a hold of the Multi-Cal system and set it up to attempt to reproduce the issue. 

Please provide all the information above and allow a few days.

Thank you and Regards,

Luis 

Luis,

Thanks so much for the thorough reply.  Here are the answers to your questions:

1)  OWD is NOT enabled though when i pressed "read EEPROM" on the program, the check box that says "Iout+OWD?" was checked.

2) I've attached the precal file for the 4-20mA unit. 

3) My multi-cal system did not come with a PGA309 test card.  I've asked about this before and was told this wasn't available.  If it is, how can I get one? A test card would be VERY helpful in debugging these kind of issues. 

4) I believe I've resolved the communication issue with the voltage board.   The jumper cable connected the common of the two power supplies seemed to be loose/faulty.  Once i replaced this, communication worked with no issue. 

[PGA309_Settings]
Numb Reg=3    
Poly Order=2    
Output Mode=2    
Vout_High_Target=3.803221    
Vout_Module_High_Target=0.000000    
Vout_Module_Low_Target=0.000000    
Iout_High_Target=0.020000    
Iout_Low_Target=0.004000    
Vout_Low_Target=0.395221    
Vs=5.000000    
Vref=4.096000    
Calibrate Nonlin=TRUE    
Calibrate Coarse Offset=TRUE    
Reg0=0    
Reg1=0    
Reg2=0    
Reg3=1280    
Reg4=0    
Reg5=0    
Reg6=1027    
Reg7=0    
Reg8=0    
Temp0=-35.000000    
Temp1=25.000000    
Temp2=80.000000    
XTR_R1=11300.000000    
XTR_R2=10000.000000    
XTR_R_ref=191000.000000    
XTR_Vref=4.096000    
Secondary Output Stage=FALSE    
Second Stage Gain=1.000000    
Second Stage Offset=0.000000    

Hi Avi,

By PGA309 test card, I was referring to the Custom PGA309 + sensor board schematic you are currently using.  Please provide your Custom sensor board PGA309 schematic showing the DSUB-9 connector to the Muti-Cal interface card connections.  If you are connecting using the screw terminal block, please show a diagram of the terminal block to Muti-Cal Interface connections.  If you don't wish to share the schematic publicly, you could start a private conversation

Since TI already offers the PGA309EVM-USB for Customer evaluation, there is no PGA309 test card board offered on TI Store. However, if you wish, I could look into provide you a PGA309 test card Altium design files of a prototype if you are interested via private conversation.

Thank you and Regards,

Luis

Thanks Luis.  PM sent.

Hi Patel,

Thank you.

I will review in detail and attempt to reproduce on the lab.  Please allow a couple of business days to access and setup the system.

Kind Regards,

Luis