Data recovery procedure using DC offset and gain control for timing loop compensation for partial-response data detection

摘要

Apparatus and method of data recovery are provided for data detection in a partial-response (PR) data channel. The PR data channel includes an analog-to-digital converter (ADC) for providing digital samples of a readback data signal and a voltage controlled oscillator (VCO) timing control coupled to the ADC. A data recovery procedure (DRP) is established responsive to a detected readback error. Using amplitude offset circuitry, amplitude of the readback data signal is selectively adjusted responsive to the detected readback error; and using gain control, a correction current applied to the VCO timing control is changed responsive to the detected readback error.