Other Parts Discussed in Thread: ADS5474
I am working with the TSW1400EVM with the ADS5474 eval module. The sample rate for the design I am evaluating is 50 MHz. When I attempt to trigger acquisition using the external trigger option with "arm on next capture button press" activated, the detection of the trigger event is very inconsistent. Sometimes a trigger is detected, other times the software gives up and says that no trigger was detected. When I speed up the sample clock to 400 MHz, the trigger is detected 100% of the time. I guess I'm missing something as to how the trigger signal is detected or maybe my signal is ill-timed. The signal I am using as the external trigger is asynchronous to the sample clock and is a periodic pulse train of period 120 ms, pulse width 1.5 us with edge transitions of 5 ns. Also, the high and low logic levels for this trigger signal are 3.3V and 0V, respectively. Can you tell me if this signal is suitable and if so, what else could be giving rise the the lack of trigger detection for 50 MHz sample rate?
