A PRML AND EPRML SPLICED OPERATION SCHEME DESIGNED TO REDUCE POWER DISSIPATION OF READ CHANNEL CHIPS

In order to reduce the power dissipation and the circuit size for read channel chips, two techniques are proposed. One is based on the splic ed operation of two different channel signaling methods such as PRML a nd EPRML. These two detectors are operated selective in correspondence with the value of the reliability information extracted from the data series. The other is an extended method which applies the transformed trellis simplification technique to a RADIX4 detector. These are effe ctive for implementing a high data transfer rate. We have confirmed th at the total detector power dissipation including PRML, EPRML and addi tional circuits is reduced to less than half of the conventional EPRML power dissipation, while achieving twice tha data transfer rate of th e conventional EPRML.