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:
Jan. 13, 2009
Filed:
Nov. 09, 2004
Hiroshi Yamaguchi, Osaka, JP;
Masaki Taniguchi, Kyoto, JP;
Hiroshi Yamaguchi, Osaka, JP;
Masaki Taniguchi, Kyoto, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An operational amplifier including a pair of differential input transistors is provided with a feedback resistor switching circuit and a variable current source. When a loaded optical disk is a DVD-ROM, the feedback resistor switching circuit reduces a gain of the operational amplifier and the variable current source selects a large current (of, for example, 1 mA) as a common bias current supplied to the differential input transistors. When the loaded optical disk is a DVD-RAM with low reflectance and low recording/reproducing speed, the feedback resistor switching circuit enhances the gain of the operational amplifier and the variable current source selects a small current (of, for example, 0.5 mA) as the common bias current.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile