Continuos Squarewave generation LV not seeing failures

[Branderegg]

Hi,

I am using a PXI-6723 to output squarewaves to my UUT. These waves are continuously generated at a rate of 30Hz. The waveforms do what I need them to do inside the UUT but I ran into a failure with an IC within my UUT. What the failure does is causes the signal to ring inside the UUT. This signal is processed by my unit then changed into a CAN message. Im observing the CAN message to verify the unit is operating correctly. This ringing causes the CAN message to double. My problem with labview is with the Ao I am using the waveform I create acts like it doesnt ring. I have another test station where you can tell the signal is ringing and the unit fails but with labview the unit passes all testing even though we have measured the ringing inside of the node. I have tried many possible solutions and I am exhausted of ideas. Any ideas?

Thanks,

Brandon

[ColeTrain]

Hello Brandon,

When you set up an analog output, your task will only throw an error if there has been a problem generating the signal.  Since that part is occurring fine, your driver will not throw any errors as to what is happening on the outside of the card.  If this is a TTL signal that you are generating, then you could use one of the counters on the card to monitor if there is any ringing.  

Also, building a current follower right before your UUT and making sure all of your impedances match could help to eliminate the ringing in the first place.  Post back if you want any help with this.