Analog CMOS implementation of high frequency least-mean square error learning circuit

A continuous-time analog CMOS circuit with external feedback amplifiers implementing the least-mean square error adaptive learning algorithm has demonstrated a frequency of operation of 80 MHz, an adaptivity of 60 dB, a minimum notch width of 20 kHz, a minimum adapt time constant of 20 /spl mu/s, and the simultaneous cancellation of two continuous-wave (CW) interferers. Auto-zeroing is used to cancel multiplier and integrator offsets. A fully monolithic adaptive filter circuit was also realized.