Asynchronous Phase Rotator Control

摘要

The present invention generally relates to centering a clock edge at or near the center of a data eye. Data may be sent from a first device to a second device in conjunction with a clock signal. A phase rotator operating in an external clock domain governed by the clock signal received at the second device may rotate the phase of the received clock signal to sample data. The data sampled in the unstable external clock domain may be transferred to a stable local clock domain for analysis. Feedback may be provided from the stable clock domain to the phase rotator to adjust the phase of the received clock signal to position an edge of the clock signal at or near the center of the data eye.