250 MHz digital FIR filters for PRML disk read channels

Digital FIR filters are key components of state-of-the-art partial-response signaling maximum-likelihood detection (PRML) read/write channel ICs but consume significant circuit area and power. These 10-tap and 8-tap, 6b filters provide PR-IV channel equalization at 20+MB/s data rates. Achieving these data rates while reducing power and area requires an optimized distributed arithmetic (DA) architecture combined with custom circuit design and layout. These filters improve attainable data rate by a factor of about 1.5 and power and area consumption by a factor of two, compared with standard-cell-designed filters using the same architecture and technology.