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:
Dec. 30, 2014
Filed:
Feb. 13, 2013
Applicant:
Megachips Corporation, Yodogawa-ku, JP;
Inventors:
Takashi Ikeda, Chiba, JP;
Masato Yamaguchi, Naha, JP;
Assignee:
MegaChips Corporation, Yodogawa-ku, JP;
Primary Examiner:
Int. Cl.
CPC ...
G06G 7/19 (2006.01); H03K 17/14 (2006.01); G01R 27/02 (2006.01);
U.S. Cl.
CPC ...
H03K 17/145 (2013.01); G01R 27/02 (2013.01);
Abstract
A first constant voltage is supplied to a variable capacitance in a switched capacitor, and the variable capacitance is effectively charged to the first constant voltage in each cycle of a sampling clock. A current generated by charging the calibration resistance is averaged, and a resultant current is compared against a current generated by applying a second constant voltage to a resistance. The capacitance value of the variable capacitance is adjusted in accordance with a result of the comparison. Thus the variable capacitance is calibrated so as to have a target value.