MCM-113 was originally tested 19-Jul-99. It failed because "only one block of 32 channels (1st) responds to Vcal, serial readback doesn't work, come back when we are convinced the setup works well and test this again."

On 6-Aug-99 it was tested again with the latest Xilinx programs (mcmc6.hex and mcmr8.hex). The only difference in the results was that I could not get any of the channels to respond to Vcal this time.

None of the AMU spy lines worked (MUX2) on the whole MCM. All of the preamp spy lines (MUX1) worked and seemed to respond correctly to bench-cal input. Almost all of the channels were always overflow and those that were not overflow are close. Raw mode gave both pre and post samples which were always overflow (3FF) or close to overflow.

I looked at the ramp for AMU/ADC chip 1. It looks terrible:

The top of the ramp should be at Vref (2.97 V in this case) and the slope should be much flatter (Iref=7.4). The ramp looked about the same when the setup DACs were completely different (Vref=4.5, Iref=60). It does not appear to respond to either of these DACs correctly and this looks like the reason the MCM does not work. The ramp should look something like this (notice the different scale from the plot above):

This was checked again 24-Aug-99. No significant changes were seen. None of the channels respond properly to bench-cal. (Unlike the previous test) the preamp spy channels to not respond correctly to Vcal input. In fact, I was unable to turn the spy channel output off. There is a signal with the right shape, but it can not be turned off and does not respond to bench-cal. The serial readback does not work except for TGV#8. All channels returned ADC=3FF or close to 3FF.