Patent ID: 6044053
Filing Date: 2000-03-28
Classification: G11B

Abstract:
A dc balance-value calculation circuit, used in a recording signal generator for performing the block coding of original data to generate a code word having a series of at least two non-inverted bits and generating a recording signal based on said code word, provided for calculating a dc balance value representing a shift in the dc balance of said recording signal,in which said dc balance-value calculation circuit includes:selection means for separating said code word generated by the block coding into unit data of a plurality of bits, and selectively outputting said unit data;determination means for determining a change in a dc balance value for each unit data, based on said unit data output by said selection means;and dc-balance-value calculation means for calculating a dc balance value in accordance with the determination result by said determination means, wherein said determination means includes a logical circuit for outputting a signal representing the change in the dc balance value by carrying out a logical operation based on said unit data output by said selection means and the condition of said recording signal at the termination of previous unit data, wherein said dc-balance-value calculation means includes an 11-bit counter for performing a count operation in accordance with the signal output by said logical circuit.