Time measurement in automatic test equipment

Abstract From the Canadian patent

Apparatus for automatically testing electronic circuits and performing time measurements, including a time measuring circuit for counting clock pulses provided between stop and start event edges presented to it, two independent input selectors for each selectively connecting one of a plurality of its inputs to the time measuring circuit and a plurality of, local comparators located within the test apparatus near sources of signals to be timed and generating an event edge upon receiving a signal crossing a threshold value. Also dislcosed are making time measurements of signals at digital and analog pins using local comparators connected to input selectors over deskewed transmission paths and …