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. 15, 2011
Filed:
Feb. 15, 2007
Kenichi Shinbo, Yokohama, JP;
Fujio Oonishi, Yokohama, JP;
Ritsuro Orihashi, Tokyo, JP;
Yasushi Terui, Tsuchiura, JP;
Tsukasa Shishika, Hitachinaka, JP;
Kenichi Shinbo, Yokohama, JP;
Fujio Oonishi, Yokohama, JP;
Ritsuro Orihashi, Tokyo, JP;
Yasushi Terui, Tsuchiura, JP;
Tsukasa Shishika, Hitachinaka, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
In a data acquisition system of ADC system, a log amplifier is provided at the pre-stage of an A/D converter, a signal amplified by the log amplifier having a nonlinear input-output characteristic is A/D-converted, and an adding operation of data is performed while reconverting a voltage value data which is converted to a nonlinear characteristic to data with a linear scale according to a table memory for reverse-log conversion. A known voltage value is inputted into the log amplifier to perform measurement, and calibration of the table memory is performed by storing the voltage value and the voltage value data after A/D-converted.