Distributed arithmetic digital filter in a partial-response maximum-likelihood disk drive system

摘要

A 10-tap finite impulse response (FIR) digital filter is provided in a partial response signaling and maximum-likelihood (PRML) data channel. A plurality of partial sums of predetermined tap weights are stored in a palette random access memory (RAM). A fixed qualifier value is received and used together with selected ones of the stored partial sums for calculating a predetermined tap weight. Predetermined filter coefficients are calculated and stored in a filter RAM using the calculated predetermined tap weight and predefined ones of the stored partial sums.