Hi Everyone,
I have been working on a test fixture that uses synchronous AI and AO with my PCI-6052E. I output a waveform consisting of several linear ramps to my circuit and then read circuit variables with the AI channels. I have a scan rate equal to the update rate, and I have monitored the output on a scope, it looks good.
My problem is that my AI channel has many steps instead of a fairly smooth line. I think the 6052E has a resolution of ~384 uV worst case, I am seeing something like 70 mV! I need to measure at least 0 - 10 V.
Another note, in order to test the card / setup I removed everything from my setup and wired the AO directly into the AI channel. Next I changed my linear ramp to be very slow (0 - 1 V in
3 seconds), while maintaining a 4 kHz scan and update rate. Next I adjusted the channel limits (gain on the card). I saw that with default limits I saw 70 mV steps, and as I adjusted the gain on the card the steps decreased significantly. Once I was down to 0 - 1 V limits the AI matched the AO pretty well (although it still may have been greater than 384 uV steps).
I am looking for some kind of suggestion as to what is wrong with my system. My tests lead me to believe it is a problem with the PCI-6052E card.
Thanks for any help,
nord
