Patent ID: 7751295
Filing Date: 2010-07-06
Classification: G11B

Abstract:
1. An optical disk device that performs analog-to-digital conversion of a reproduction signal made by reproducing a signal recorded in an optical disk, the optical disk device comprising: an analog equalization circuit having an equalization characteristic of enhancing a predetermined frequency band of the reproduction signal and attenuating an unnecessary frequency band; an analog-to-digital converter that performs analog-to-digital conversion to an analog equalization signal equalized by the analog equalization circuit; a digital equalization circuit that adjusts a frequency characteristic of a reproduction signal digitized by the analog-to-digital converter; and a PRML decoding circuit that decodes a digital equalization signal equalized by the digital equalization circuit, wherein: the digital equalization circuit is configured in a way that it has a signal characteristic detector that detects a signal characteristic of the digitized reproduction signal, and controls the equalization characteristic of the analog equalization circuit depending on a detected signal characteristic, and the signal characteristic detector is configured in a way of further controlling an equation characteristic of the digital equation circuit depending on the detected signal characteristics.