An analog forward equalizer for MDFE read channel

Abstract

The design and implementation of an analog forward equalizer for MDFE (multi-level decision feedback equalization) read channel is described, for use in magnetic recording applications. The equalizer is realized as the cascade of two biquadratic Gm-C filters. Transconductor operating in the triode region is used to achieve good linearity. The circuit is fabricated using AMS 0.6-um 3-metal-2-poly CMOS technology with a single 3.3-V power supply. The simulation results, for the case of 2.5 user density and 66Mbits/sec data rate, show that the dipulse response at the forward equalizer output and the detection SNR at the slicer input closely matches the theoretical results.