• TI thinks resolved

PGA309: USB DAQ Platform

Part Number: PGA309

I have a DAQ board connected to a multi-cal master board with PGA0309  boards on the interface board.
All cables seem correct
I have them set for 4 wire voltage mode, and I select the 4 wire voltage mode model in the software.
my supplies are on, the +9V to the DC jack, the USB is plugged in, the
15/-15V and 5V that supplies the DUT
the corresponding  LED's light up,
I set up 4 temperature points. After scanning, the LED corresponding to Vdut is always bright, and it can complete the calibration of the initial temperature. However, after a certain temperature calibration, all calibration paths (8 ways) fail. At this time, the Vdut corresponding LED will go out. I measured the voltage between Vdut and GND and found that it was already no longer in 5V and turned into a 0V. By looking at USB DAQ Platform USER 'S Guide, I know that Vdut has been disconnected.           
This happens so often that the calibration of the sensor can not be completed. However, as long as I shorten the time between the temperature points, the frequency of this situation can decrease.          
 By looking at USB DAQ Platform USER 'S Guide, I know that the software setting disconnects the Vdut.           
I want to know why Vdut is interrupted in the calibration process so that it can't be calibrated.
I would like to know how to avoid Vdut being disconnected from the calibration process.  

  • Hi user4164924,
    This power off is being commanded by software, and may be a bug. What version of the PGA309 multi-cal software are you using? Does the failure always occur at a specific temperature (50°C, for instance) or a specific temperature number (like the 3rd temperature configured)? Any information you can provide to help us reproduce this would be appreciated.

    Regards,

    Alex Davis

    Precision Amplifier Applications - TI Tucson

  • In reply to Alexander Davis:

    Hi sir

    The version I'm using now is V2.3i, and the previous version  is V1.6b. These two versions all have this problem. This situation appears at second, third, fourth temperature points and has nothing to do with the temperature point.  I think this is likely to be the case with too long calibration time, usually from fourth to fifth hours. When a failure occurs, Dut Power and Vdut dischange (TP29) will become high levels, and Pull up (TP25) and Disconnect one (Tp27) will become low levels.
    Before starting calibration today, I force Dut Power and Vdut dischange (TP29) onto GND, and Pull up (TP25) and Disconnect one (TP27) are forced to VCC. Two calibration cycles have been completed today, and there is no mistake for the time being.
    I think it's a problem with the software.           
    1. would you please help to confirm that my practice is feasible?           
    2. can you help to provide code or update software?           
    3. can you help to provide the specification  of the V2.3i version, and about the TEST/DEbug and other functions of the software,I do not yet know how to use them.           
    The attached map is the software interface after the error.           
    Thanks very much

  • In reply to user4164924:

    Hi user4164924,
    1. I don't see any issues with your approach.
    2. Unfortunately, V2.3i is the latest version of the software.
    3. The Test/Debug page of the software provides control over DUT power (through the switching circuitry on the USB-DAQ), measurement MUX, and provides diagnostics to list attached VISA devices (DMMs, for example). It also allows you to reinitialize the software to its startup default settings, if necessary.

    I'll look into the software to see if I can find the issue, and will update this thread with a better answer then.

    Regards,

    Alex Davis

    Precision Amplifier Applications - TI Tucson