TIME DOMAIN ANALOG MULTIPLICATION TECHNIQUES FOR ADJUSTING TAP WEIGHTS OF FEED-FORWARD EQUALIZERS

摘要

Feed-forward equalizer (FFE) circuits and methods are provided which implement time domain analog multiplication for adjusting FFE tap weights. For example, a method includes inputting data signals to FFE taps of a current-integrating summer circuit, wherein the data signals are time-delayed versions of an analog input data signal. A capacitance is charged to a precharge level during a reset period of the current-integrating summer circuit. An output current is generated by each FFE tap during an integration period of the current-integrating summer circuit. The output currents from the FFE taps collectively charge or discharge the capacitance during the integration period. A gating control signal is applied to a given FFE tap during the integration period to enable the given FFE tap during a portion of the integration period in which the gating control signal overlaps the integration period so as to effectively multiply the data signal input to the given FFE tap with an FFE coefficient value corresponding to a period of overlap between the gating control signal and the integration period.