Implementation of a digital read/write channel with EEPR4 detection

A fully integrated digital read/write channel for magnetic recording applications is described. The device employs partial response maximum likelihood (PRML) sequence detection when reading data to enhance bit error rate vs. signal-to-noise ratio performance. The sequence detector is designed to accept input pulses exhibiting four non-zero samples, sampling occurring once per channel bit time. Channel optimization is facilitated through the inclusion of sixty-two 8-bit registers. The device is fabricated in a 0.8 micron double-metal CMOS process and supports data rates as high as 64 Mbits/sec.<
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