Analog Output channel broken

[Optoelec]

Hi All,

I am using my NI USB-6343 to generate four arbitrary analog output signals, which are then sent to four op-amps to be amplified up to a maximum of 120V. Recently, I noticed that one of the output channels is no longer functioning—it does not generate the programmed signal. Testing via the NI test panel confirmed that all channels work except for this one.

Does anyone have any idea what might have caused this issue and whether it’s possible to repair it at home? It’s worth mentioning that the corresponding op-amp was also damaged (burned). However, according to an electrician colleague, this is unlikely to have caused the AO channel to fail.

Any insights or suggestions would be greatly appreciated.

Best regards,

Reza   

[santo_13]

Definitely, the failure of the OPAMP triggered the failure of the channel. You need sufficient fail-safe mechanisms to protect the DAQ since the OPAMP deals with voltage levels over the maximum rating of DAQ. I suspect some kind of OPAMP failure fed the high voltage back into the DAQ AO, causing it to fail.

You can implement crowbar circuits between DAQ and OPAMP to ensure any failure on the high voltage side doesn't damage the DAQ.

If you're an electronics expert with hardware debugging skills and equipment, you may be able to fix it, otherwise, not worth the time.