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:
Feb. 08, 2005
Filed:
Jan. 30, 2003
Yoshihisa Fujimoto, Nara, JP;
Yoshihisa Fujimoto, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
In the hold phase, two negative feedback circuits constituted by the negative feedback capacitorsandand two positive feedback circuits constituted by positive feedback capacitors are provided between an input terminal and an output terminal of an operational amplifier. Here, in a sampling phase before a hold phase, charges according an input signal Vis stored in each of the capacitors, and charges according to an input signal Vare stored in each of the capacitors. As a result, a gain of the switched capacitor amplifier circuit is derived from (Ca+C)/(Ca−Cx) wherein Ca indicates an electrostatic capacitance of the negative feedback capacitors, and Cx indicates an electrostatic capacitance of the positive feedback capacitors, and thus the gain can be increased without significantly increasing an electrostatic capacitance ratio.