Information reproduction device and read clock monitoring method

Abstract

An information reproduction device capable of a more appropriate frequency monitoring of a read clock, as compared to conventional devices, is realized. By providing the information reproduction device with a frequency difference detection means which detects a difference in frequencies between a read clock, obtained by applying PLL to a reproduction signal read from a recording medium, and a reference clock; an information processing means which performs signal processing on the reproduction signal and outputs a processing status information indicating whether or not the information processing is performed normally; and a frequency monitoring means which monitors whether or not the frequency of the read clock is normal based on the frequency difference and the processing status information; wherein the frequency monitoring means makes a transition to an OK status which indicates that the frequency of the read clock is normal when the processing status information is indicating a normal status; and makes a transition to a NG status which indicates that the frequency of the read clock is abnormal when the processing status information is indicating an abnormal status and the difference of the frequencies exceeds a first threshold; and returns to an OK status when the difference of the frequencies is below a second threshold during the NG status.