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. 13, 2011
Filed:
Mar. 24, 2010
Yoshimi Iso, Tokyo, JP;
Kakeru Kimura, Tokyo, JP;
Tadashi Matsushima, Tokyo, JP;
Yuji Shimizu, Tokyo, JP;
Yoshimi Iso, Tokyo, JP;
Kakeru Kimura, Tokyo, JP;
Tadashi Matsushima, Tokyo, JP;
Yuji Shimizu, Tokyo, JP;
Renesas Electronics Corporation, Kawasaki-shi, JP;
Abstract
In AD conversion of a voltage under measurement, data continuity is ensured between the result of conversion after amplification by using an amplifier circuit and the result of direct conversion without using the amplifier circuit. In AD conversion operation using a DA converter circuit, an amplifier circuit, and an AD converter circuit under the direction of a control circuit, an analog signal output from the DA converter circuit is directly converted by the AD converter circuit, and also the analog signal is converted therein after amplified by the amplifier circuit with an expected gain of 2('n' represents a positive integer). Based on resultant data thus obtained, a gain of the amplifier circuit and an offset thereof are calculated. An analog signal under measurement to be enhanced in bit precision is subjected to amplification by the amplifier circuit and conversion by the AD converter circuit, the offset calculated as mentioned above is subtracted from the result of the conversion, and the result of the subtraction thus performed is multiplied by a ratio of the expected gain to the gain calculated as mentioned above so as to cancel a gain error. Then, based on data with the gain error canceled, acquisition of bit-extended conversion result data is performed to ensure continuity between data having different degrees of bit precision.