The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 17, 1991
Filed:
Jul. 12, 1989
Hidehiro Ishii, Saitama, JP;
Noriyoshi Takeya, Saitama, JP;
Chiharu Miura, Saitama, JP;
Tatsuya Fukuda, Saitama, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
A disc player having digital processing of error signals in a servo system utilizes an A/D converter. The relatively small closed loop error signals are amplified by a predetermined amount above that for the open loop error signals prior to conversion in the A/D converter, and the converter output representing the digitized small error signals are amplified by a predetermined amount below that for the digitized open loop error signals. While the overall gain in the servo system is substantially the same for the closed loop and open loop error signals, the small closed loop error signals are greatly expanded in range at the converter input to permit the same A/D converter to faithfully convert both the open loop and the closed loop error signals.