Patent ID: 6879549

Claim:
A brake signal generating circuit comprising: a brake signal generator which receives a mirror signal that detects the track movement of a main beam and generates one of a first brake signal and a second brake signal for selecting predetermined operation mode signals in response to a first brake selection signal; a first operation mode generator which generates a processing value of the gain and phase of a tracking error as a first operation mode signal in response to a predetermined first control signal; a second operation mode generator which generates a correction value of a tracking loop offset as a second operation mode signal in response to a predetermined second control signal; a third operation mode generator which generates a value obtained by multiplying a value of the first operation mode signal by a predetermined value K 1 , where K 1 is a non-zero real number, as a third operation mode signal; a fourth operation mode generator which generates as a fourth operation mode signal a value obtained by subtracting the value of the first operation mode signal from a value of the second operation mode signal, multiplying the result of the subtraction by the predetermined value K 1 , and adding the value of the second operation mode signal to the product; a fifth operation mode generator which generates a predetermined reference voltage as a fifth operation mode signal; and a switch unit which outputs one of the first through fifth operation mode signals in response to one of the first and second brake signals and second through fourth brake selection signals.