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. 31, 1996
Filed:
Apr. 11, 1995
Yukio Ono, Hyogo, JP;
Seiichiro Kikuyama, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A sensor drive circuit which accurately detects the amount of variation in inductance of a coil serving as a variable sensor. A peak detector circuit detects a peak value of a difference signal between a variable-amplitude signal and an intermediate signal to output a peak detection signal as a verification signal to a first input of an error amplifier. The error amplifier has a second input receiving a reference voltage and outputs a control signal to an AGC circuit on the basis of the result of comparison between the peak detection signal and the reference voltage. A peak detector circuit detects a peak value of a difference signal between the variable-amplitude signal and an inverted variable-amplitude signal to output the peak value as an inductance detection signal to the exterior. The AGC circuit performs automatic gain adjustment to output a signal of determined amplitude to a buffer in response to the control signal from the error amplifier.