The present invention relates, in general, to integrated circuits and, more particularly, to equalization of an input signal in an integrated circuit.
Data transmission over a communication channel requires differentiation of received data between a logic one and a logic zero data value. Communication channels suffer from lossy interconnect paths that cause distortion of signal waveforms. To correct for signal distortion and allow recovery of received data, signals at the input of a receiver are equalized to restore the effects of the communication channel on the transmitted signal.
An equalizer circuit receives a transmitted data signal and compensates for signal losses by restoring the original frequency content of the signal. The amount of equalization that is necessary to compensate for signal loss is dependent on the frequency of the data signal, channel loss characteristics, and the strength of the transmitted signal. Equalizer circuits that only provide a constant equalization of the received signal improperly compensate for varying communication channel loss.
Accordingly, it would be advantageous to have an equalization circuit and method that provides a low error rate in the differentiation of logic one and logic zero data values. It would be of further advantage to provide an equalization circuit that independently adjusts the amount of equalization such that the channel loss is offset. The equalization circuit should adapt to correct for a range of expected channel losses. Furthermore, the circuit should be expandable to accommodate multiple data channels rather than a single data channel.