| 摘要 |
PURPOSE:To make the range of phase error detection constant, by comparing the average signal of peak values of an integral differece signal and the integral difference signal with each other. CONSTITUTION:A read signal P from a recording medium and a reference signal from a phase synchronizing oscillator 1 are inputted to an EOR circuit 3, and a coincidence signal (a) and a dissidence signal (b) are inputted to an integrating circuit. A coincidence integral signal A and a dissidence integral signal B are given to a differential amplifier 5, and an integral difference signal D is outputted and is given to a comparing circuit 6 through a transistor TrT1. Meanwhile, the signal D is inputted to a TrT2M to obtain an average voltage of the signal D. This average voltage is given to a voltage dividing circuit (R3+R4) through an amplifier 8 to obtain a reference voltage V0. The reference voltage V0 is compared with the integral difference signal D by the comparing circuit 6 to detect a phase error. Thus, the range of phase error detection becomes constant. |
