Calibration thermal drift

[damercer]

Hi: This is as much or more a hardware issues as it is Scopy software issue. The thermal drift of the gain/offset of either the analog in and/or analog out can be large enough to cause the following: Shortly after powering up the m2k I ran Scopy and did a second connect after a sew seconds to get a "valid" calibration. With AWG 1 amplitude set to 10 V, both scope channels displayed more or less correct p-p values. After running for a long time I noticed the displayed p-p amplitude had drifted down to less than 9 v p-p so I forced it to calibrate again. Now the sine wave output is clipped as we see here: We probably need to take a closer look at the thermal drift issue. Is there enough calibration range and/or too much drift as the board heats up?

I know the new design used significantly less power but still might be worth taking another pass at the drift issue before we lock in the production design.

Doug