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:
Aug. 09, 2005
Filed:
Apr. 14, 2003
Takashi Oshima, Saitama, JP;
Kenji Maio, Tokyo, JP;
Takashi Oshima, Saitama, JP;
Kenji Maio, Tokyo, JP;
Renesas Technology Corporation, Tokyo, JP;
Abstract
A gain-control method and device that enable high-speed gain switching of cascaded programmable gain amplifiers (PGA) without a high-resolution A/D converter is provided. In one example, the gain-control method for cascaded PGAs detects all the input levels of the PGAs, calculates the optimum gains of the PGAs each on the basis of the detection results, and sets the obtained optimum gains of each of the PGAs at one time, whereby high-speed gain switching becomes possible. The gain-control device for cascaded PGAs that implements this gain-control method includes peak hold circuits that retain the input levels of each of the PGAs, a switch group that sequentially switches outputs of the peak hold circuits, an A/D converter that sequentially detects the outputs from the switch group, and a control and operation device that calculates the optimum gains of the PGAs from the detection results by the A/D converter to set the calculated optimum gains simultaneously to each of the PGAs.