Title:
SERVO CIRCUIT FOR DISC REPRODUCER
Document Type and Number:
Japanese Patent JPS5845666
Kind Code:
A
Abstract:
PURPOSE:To prevent skipped tracking and out of focus due to the failure of a disc, by controlling the tracking or focusing, based on a detection signal being amplitude-limited which is obtained at a limiter restricted with an output voltage of a low pass filter. CONSTITUTION:A limiter 22 amplitude-limiting a detection signal VA is inserted between a subtractor 6 to obtain the tracking error detection signal VA and a servo amplifier 7. A low pass filter 21 picking up a low frequency component of the detection signal VA is connected to an output side of the subtractor 6 and an output voltage Vc of the filter 21 is applied to a voltage follower 25 of the limiter 22. Thus, the signal VA including noise is amplitude-controlled within a range where the output voltage Vc of the filter 21 is added or subtracted with a voltage drop of a diode array 24. That is, a tracking error detection signal VB including the suppressed noise is given to a driving means 8 via an amplifier 7.
Inventors:
YOSHIDA TADAO
Application Number:
JP14060781A
Publication Date:
March 16, 1983
Filing Date:
September 07, 1981
Export Citation:
Assignee:
SONY CORP
International Classes:
G05D3/12; G11B7/09; G11B21/10; (IPC1-7): G05D3/12; G11B7/08; G11B21/10
Attorney, Agent or Firm:
Sadaaki Kambara