Patent ID: 8509299

Claim:
An apparatus including a decision feedback equalizer operable with a plurality of data rates, comprising: decision feedback equalization circuitry responsive to an incoming data signal, a retiming clock signal and a controlled clock signal by providing a retimed equalized data signal, wherein said incoming data signal has associated therewith a data clock having a data clock rate equal to one of a plurality of data clock rates; and clock circuitry coupled to said decision feedback equalization circuitry and responsive to a clock signal Corresponding to said data clock by providing said retiming clock signal and said controlled clock signal, wherein said retiming clock signal has a retiming clock rate equal to said data clock rate, said controlled clock signal has a controlled clock rate equal to said data clock rate and a controlled clock duty cycle proportional to said data clock rate; wherein said retiming clock signal has a fixed retiming clock duty cycle; wherein said controlled clock signal has a fixed asserted signal state duration; said decision feedback equalization circuitry is further responsive to said incoming data signal, said retiming clock signal and said controlled clock signal by providing an equalized data signal; said retimed equalized data signal corresponds to said equalized data signal; and said apparatus further comprises clock data recovery circuitry coupled between said decision feedback equalization circuitry and said clock circuitry, and responsive to said equalized data signal by providing said clock signal; and also wherein said decision feedback equalization circuitry comprises: combining circuitry responsive to said incoming data signal and at least one or more equalization feedback signals by providing an equalized data signal; first retiming circuitry coupled to said combining circuitry and responsive to said equalized data signal and a retiming clock signal by providing said retimed equalized data signal; second retiming circuitry coupled to said first retiming circuitry and responsive to said retimed equalized data signal and said controlled clock signal by providing one or more additional retimed equalized data signals; and feedback circuitry coupled to said second retiming circuitry and responsive to said one or more additional retimed equalized data signals by providing said one or more equalization feedback signals.