Patent ID: 7848394
Filing Date: 2010-12-07
Classification: H03M,H04J,H04L

Abstract:
1. A device for generating a test signal in a serial transceiver, comprising: a first serial transceiver having a reference clock, a first receiver, and a first transmitter, said first receiver including (i) a phase detector, and (ii) a phase rotator driven by said reference clock; a first multiplexer coupled to said first receiver, wherein said first multiplexer is configured to receive (i) a phase detector output and (ii) a control signal, and wherein said first multiplexer is configured to pass said control signal to said phase rotator when said first serial transceiver is in a test configuration, thereby varying a frequency of said phase rotator output; and a second multiplexer coupled to said first transmitter, wherein said second multiplexer is configured to receive (i) said reference clock and (ii) said phase rotator output, and wherein said second multiplexer is configured to pass said phase rotator output to said first transmitter when said first serial transceiver is in said test configuration, thereby causing said first transmitter to transmit a serial data stream that varies in frequency from said reference clock.