Timing skew characterization apparatus and method

摘要

A timing skew characterization apparatus comprises a coarse timing skew characterization circuit, a fine timing skew characterization circuit and a coarse delay cell calibration circuit. The coarse timing skew characterization circuit comprises a plurality of coarse delay cells whose delays can be calibrated through the coarse delay cell calibration circuit. The calibration of fine delay cells can be implemented through a trail and error process. Both coarse delay step and fine delay step can be characterized through a single measurement setup. As a result, the timing skew characterization apparatus provides a high resolution setup and hold time measurement.

主权项

1. An apparatus comprising:
a coarse timing skew characterization circuit having a buffer chain, a buffer of the buffer chain including a propagation delay; a coarse delay cell calibration circuit configured to measure a delay between an input of the buffer chain and an output of the buffer chain; and a fine timing skew characterization circuit connected between the coarse timing skew characterization circuit and a device-under-test (DUT), wherein a delay time of a fine delay step of the fine timing skew characterization circuit is determined based upon a setup and hold time of the DUT.