Array Transfer Curve Measurement

Curtis repeated the source follower transfer function measurement at our latest operating point, plotted below.  The measured gain is the same as what we used at the IRTF, but the curve itself is offset by a few tens of millivolts.

We see about 8kDN/V, so the rail-to-rail source-follower swing of 1.6V is worth 13kDN or ~450k electrons @ 35 e/DN .  This would be an upper limit on well capacity, but some other factor will likely limit us to a smaller value.

The point of this measurement is to verify that we're operating in the linear range of the source follower, and that the changes we've made to remove the glow and odd/even effect have left us with a usable range.  The changes to the operating point haven't changed anything much.

For reference, here is our present optimization of the array operating point: