CIRCUIT AND A METHOD FOR DETECTING AN ADIP SIGNAL OF A WOBBLE DETECTING SYSTEM OF OPTICAL DISC APPARATUS, PARTICULARLY CONCERNED WITH CORRECTLY AND QUICKLY DETECTING NON-CONTINUOUS POINTS IN THE ADIP SIGNAL

摘要

PURPOSE: An ADIP(Address in Pre-groove) signal detecting circuit and method is provided to exactly and quickly detect non-continuous points, and to easily implement an integrated circuit. CONSTITUTION: The circuit comprises a delayer(31), the first window comparator(32), the second window comparator(33), the first edge detector(34), the second edge detector(35), the first non-continuous point checker(36), and the second non-continuous point checker(37). The delayer(31) delays a wobble signal by a predetermined time. The first window comparator(32) compares the wobble signal with a positive reference level and a negative reference level, and outputs the first comparison signal and the second comparison signal. The second window comparator(33) compares an output signal of the delayer(31) with the positive reference signal and the negative reference signal, and outputs the third comparison signal and the fourth comparison signal. The first edge detector(34) receives the first and the third comparison signal, and detects edges of the first comparison signal. The second edge detector(35) receives the second and the fourth comparison signal, and detects edges of the second comparison signal. The first non-continuous point checker(36) generates a signal corresponding to a positive non-continuous point of the wobble signal if there exist two continuous edges within a certain time interval among the edges detected by the first edge detector(34). The second non-continuous point checker(37) generates a signal corresponding to a negative non-continuous point of the wobble signal if there exist two continuous edges in a certain time interval among the edges detected by the second edge detector(35).