Tektronix 071-0590-00 user manual

Application Note - Auto Search Synchronization

If the error rate is above the Threshold, the next point toward the Data Eye Center will be examined, and so on, until the error rate transitions to below the Threshold. The first point below the Threshold will be the TRUE transition point.

6.After the new transition points are re-examined and the TRUE transition points are found, the delay will be set as follows:

For Case 1, the delay will be set to the middle of the two TRU transition points (point C).

For Cases 2 and 3, the delay will be set to be away from the middle of the TRUE transition points by half the data clock period (point C).

7.Eye Width Measurement

In the previous step above, if the error rate is below the threshold, the measured eye width is the point B delay measurement minus the point A delay measurement in Diagram 1, Case 1. STOP.

In the previous step above, if the error rate is above the threshold, the calculated eye width for Diagram 1 Case 2 is the delay measurement at point A minus the delay measurement at point C, times two. STOP.

In the previous step above, if the error rate is above the threshold, the calculated eye width for Diagram 1, Case 3 is the delay measurement at point C minus the delay measurement at point B, times two. STOP.

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