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:
Jun. 02, 2015
Filed:
Feb. 24, 2012
Yoshinao Yanagisawa, Ueda, JP;
Masahiro Oshio, Shiojiri, JP;
Takayuki Kikuchi, Okaya, JP;
Toshihiro Nishida, Nasushiobara, JP;
Masayuki Takahashi, Nasushiobara, JP;
Yoshinao Yanagisawa, Ueda, JP;
Masahiro Oshio, Shiojiri, JP;
Takayuki Kikuchi, Okaya, JP;
Toshihiro Nishida, Nasushiobara, JP;
Masayuki Takahashi, Nasushiobara, JP;
SEIKO EPSON CORPORATION, , JP;
SEIKO NPC CORPORATION, , JP;
Abstract
A signal processing circuit includes an I/V conversion circuit (current/voltage conversion section) that converts an oscillation current of a vibrator into a voltage, an RC filter (phase shift section) that shifts a phase of the output signal of the I/V conversion circuit, a full-wave rectifier (part of a drive amplitude control section) that binarizes a signal that has been shifted in phase to generate a switch control signal, a comparator (reference signal generation section) that generates a reference signal for synchronous detection based on the output signal of the I/V conversion circuit, and an EXOR circuit (clock signal generation section) that generates a clock signal for a switched capacitor filter (SCF) that has a frequency twice a frequency of a drive signal based on a phase difference between the reference signal and the switch control signal.