Patent ID: 7394735

Claim:
An apparatus to update filter tap coefficients for use in equalizing a waveform of an input signal, comprising: a filter unit provided with a plurality of filter tap coefficients to equalize a waveform of an input signal representing a laser beam reflected from an optical disc; a coefficient updating unit to stop the updating of the filter tap coefficients and output current filter tap coefficients to the filter unit for equalizing the waveform of the input signal, when a track jumping occurs on the optical disc during waveform equalization; a defect signal detection unit arranged to determine that the laser beam jumps between tracks on the optical disc, and to generate an update stop signal indicative thereof to the coefficient updating unit to stop the updating of the filter tap coefficients; a control unit to generate a predetermined reference voltage indicative of whether the input signal is defective to the defect signal detection unit; and an initial coefficient value storage unit arranged to receive predetermined initial filter tap coefficient values from the control unit to store the received initial filter tap coefficient values, and to output the initial filter tap coefficient values to the coefficient updating unit.