Calibrating automatic test equipment

Abstract

Calibrating automatic test equipment (ATE) includes determining an offset between a reference timing event and a channel event, where the channel event is associated with a communication channel of the ATE, and adjusting signal transmission over the communication channel based on the offset. Determining the offset may include obtaining a first time at which a reference timing signal is received at a device associated with a reference timing source, obtaining a second time at which the reference timing signal is received at a device associated with the communication channel, obtaining a third time at which a channel signal is received at the device associated with the communication channel, obtaining a fourth time at which the channel signal is received at the device associated with the reference timing source, and calculating the offset using the first time, the second time, the third time, and the fourth time.

Description

technical field [0001] This patent application relates generally to the calibration of automatic test equipment and, in particular, to calibrating test equipment channels relative to a reference timing source. Background technique [0002] Automatic test equipment (ATE) refers to automated, usually computer-driven equipment used to test devices such as semiconductors, electronic circuits, and printed circuit board assemblies. The device tested by ATE is called the device under test (DUT). [0003] In ATE, timing accuracy involves applying signals to the DUT that meet predetermined timing constraints. For example, the rising edge of a signal may need to reach the DUT within a specified time window in order to accurately test the DUT. Timing accuracy becomes even more important as the DUT operates at higher speeds because the test is typically less tolerant to signal timing variations. [0004] The timing accuracy of ATE is limited by the ATE hardware itself and the techniq...

AI Technical Summary

Problems solved by technology

However, with TDR comes a large calibration error, which is usually caused by the signal degradation of the reflected edge

That is, the signal must travel twice in the signal path (both the signal and its reflection must travel in the signal path), which results in attenuation and distortion of the signal

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