I would love to be able to trigger the scope directly on the failure case, but unfortunately falling edge trigger on CONVST is not always the failure case. It actually took quite a bit of time for me to manage to capture it on the scope even with the poor resolution shown. I am continuously sampling the ADS8556 at 5KHz (200 usec) and sometimes the failure occurs as early as the 3rd sample from power-on reset (which is the only case where I can capture it) but it has occurred randomly during operation after many many cycles. If I set my sampling interval on the scope high enough to get the detailed resolution of the event, I would be missing most events and could not guarantee capturing the one that causes the lock up. The event that I want to capture is the last rising edge of BUSY prior to the chip no longer asserting BUSY. Ideally, the ADS8556 would have a power down output signal that would tell me that I've tripped a shut down. If that existed, I could 100% capture the event every time it happens by triggering on that. Does that make sense? Is there a backdoor that would help me to trigger on the inadvertent power-down?
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