Patent ID: 8923371

Claim:
A data sampling controller for a deserializer operative for transferring from a serial data stream into a parallel data stream, comprising: an inphase data sampler configured to time inphase data samples of the serial data stream at data time intervals separated by a unit interval duration; a transition data sampler configured to time transition samples of the serial data stream at transition time intervals nominally separated from the inphase data samples by one-half of the unit interval; a decision feedback equalizer configured to apply feedback parameters to adaptively adjust the serial data stream causing asymmetry of a serial data eye defined by the serial data stream; a gear shifter configured to apply a variable skew value causing a differential timing between the inphase data samples and the transition samples, vary the skew value to cause the transition samples to track the asymmetry of the data eye, apply a first skew value during a phase locking stage while the data sampling controller synchronizes to the serial data stream, the first skew value causing a substantially quadrature relation between the data sampling clock and the transition sampling clock and apply a second skew value during a data transfer stage in response to adaptation of feedback control parameters, wherein the feedback control parameters are initialized to zero and the first skew value is set to zero during the phase locking stage and the feedback control parameters adapt to non-zero values and the second skew value is set to a non-zero value after the phase locking stage to track the asymmetry of the data eye causes by adaptation of feedback control parameters during the data transfer stage.