VITERBI DETECTOR USING PATH MEMORY CONTROLLED BY BEST STATE INFORMATION

A Viterbi detector, illustratively used in a magnetic read channel integrated circuit, provides a "final" output signal as to the most likely state of the input data signal. The Viterbi detector typically utilizes branch metric generation, add-compare-select operations, and a path memory. The best state is found prior to the final decision, and is based on the state having the lowest state metric. The best state information is used to choose an output from the path memory, so that the output data from the end of the path memory line associated with the best state is selected as the final decision of the Viterbi detector. This allows for shortening the length of the path memory in typical applications. At least one control loop may also be controlled by preliminary decisions based on the best state.