An adaptive analog noise-predictive decision-feedback equalizer

This paper describes an adaptive analog noise-predictive decision-feedback equalizer (NPDFE). It consists of an analog finite-impulse response (FIR) forward equalizer (FE), a recursive analog equalizer for noise prediction, and a decision-feedback equalizer (DFE) that uses erasure. All three analog equalizers are adaptive. Area and power are saved by using analog rather than digital equalizers because a highspeed ADC is not required and the analog equalizers used in this prototype are smaller than their digital counterparts. To demonstrate the feasibility of our proposed NPDFE, the prototype was designed for use in a disk-drive read channel.