Abstract: A clock data recovery system is described. It includes a high pass filter for transmitting a filtered data signal in response to receiving an input data signal; an adder for summing the filtered data signal with a feedback signal, wherein the adder produces a summed input signal; a plurality of clocked data comparators for receiving the summed input signal, wherein the clocked data comparators determine an input data bit value; a plurality of clocked error comparators for receiving an error signal associated with clock recovery and DFE tap adaption; an equalization and adaptation logic for selecting an error sample such that a phase associated with the error sample is locked at h0=h1+h2; and a phase mixer for transmitting a delay in response to receiving the phase and the delay is transmitted to the clocked-data comparators and the clocked-error comparators.

Abstract: A feedback module is defined to receive as input a set of data sample signals and a set of reference sample signals. Each of the data and reference sample signals is generated by sampling a differential signal having been transmitted through a FIR filter. The feedback module is defined to operate a respective post cursor counter for each post cursor of the FIR filter and update the post cursor counters based on the received sets of data and reference sample signals. Also, the feedback module is defined to generate a tap weight adjustment signal for a given tap weight of the FIR filter when a magnitude of a post cursor counter corresponding to the given tap weight is greater than or equal to a threshold value. An adaptation module is defined to adapt a reference voltage used to generate the reference sample signals to a condition of the differential signal.

Abstract: A clock data recovery system is described. It includes a high pass filter for transmitting a filtered data signal in response to receiving an input data signal; an adder for summing the filtered data signal with a feedback signal, wherein the adder produces a summed input signal; a plurality of clocked data comparators for receiving the summed input signal, wherein the clocked data comparators determine an input data bit value; a plurality of clocked error comparators for receiving an error signal associated with clock recovery and DFE tap adaption; an equalization and adaptation logic for selecting an error sample such that a phase associated with the error sample is locked at h0=h1+h2; and a phase mixer for transmitting a delay in response to receiving the phase and the delay is transmitted to the clocked-data comparators and the clocked-error comparators.

Abstract: A feedback module is defined to receive as input a set of data sample signals and a set of reference sample signals. Each of the data and reference sample signals is generated by sampling a differential signal having been transmitted through a FIR filter. The feedback module is defined to operate a respective post cursor counter for each post cursor of the FIR filter and update the post cursor counters based on the received sets of data and reference sample signals. Also, the feedback module is defined to generate a tap weight adjustment signal for a given tap weight of the FIR filter when a magnitude of a post cursor counter corresponding to the given tap weight is greater than or equal to a threshold value. An adaptation module is defined to adapt a reference voltage used to generate the reference sample signals to a condition of the differential signal.

Abstract: Apparatus for producing an oscillating signal in a predetermined phase relationship with an input signal which generates its output signal by mixing in variable proportions two or more reference oscillating signals. Preferably the reference signals should be in quadrature relationship and have approximately the same frequency as the desired output, but this is not essential. The output signal may be desired to be in phase with the input signal or to have a predetermined phase offset. In a further aspect, apparatus is described which generates quadrature related clock signals, which may be used as the reference signals in the phase-lock arrangement.

Abstract: Apparatus for producing an oscillating signal in a predetermined phase relationship with an input signal which generates its output signal by mixing in variable proportions two or more reference oscillating signals. Preferably the reference signals should be in quadrature relationship and have approximately the same frequency as the desired output, but this is not essential. The output signal may be desired to be in phase with the input signal or to have a predetermined phase offset. In a further aspect, apparatus is described which generates quadrature related clock signals, which may be used as the reference signals in the phase-lock arrangement.