Title:
PHYSICAL QUANTITY SENSOR
Document Type and Number:
WIPO Patent Application WO/2011/126033
Kind Code:
A1
Abstract:
Provided is a physical quantity sensor capable of obtaining a physical quantity detection signal with a high accuracy. The physical quantity sensor has: an oscillator for converting an externally applied physical quantity to an electrical signal; an oscillation circuit for oscillating the oscillator; and a detection circuit for detecting a signal-to-be-detected from the oscillator on the basis of a detection signal from the oscillation circuit. The physical quantity sensor further has: a Δ Σ modulator for performing a Δ Σ modulation on either one of the detection signal from the oscillation circuit and the signal-to-be-detected from the oscillator at a preceding stage of the detection circuit and outputting the modulated signal; a variable voltage source, the output voltage of which can be changed; and a control unit for controlling the output voltage of the variable voltage source. The Δ Σ modulator performs the Δ Σ modulation using a feedback signal created with reference to the output voltage.
Inventors:
TAKASE, Yasuhide (4-16-5, Saginomiya, Nakano-k, Tokyo 32, 〒1650032, JP)
Application Number:
JP2011/058657
Publication Date:
October 13, 2011
Filing Date:
March 30, 2011
Export Citation:
Assignee:
CITIZEN HOLDINGS CO., LTD. (1-12, Tanashicho 6-chome Nishitokyo-sh, Tokyo 11, 〒1888511, JP)
シチズンホールディングス株式会社 (〒11 東京都西東京市田無町六丁目１番１２号 Tokyo, 〒1888511, JP)
CITIZEN FINETECH MIYOTA CO., LTD. (4107-5, Oaza-Miyota Miyotamachi, Kitasaku-gu, Nagano 94, 〒3890294, JP)
シチズンホールディングス株式会社 (〒11 東京都西東京市田無町六丁目１番１２号 Tokyo, 〒1888511, JP)
CITIZEN FINETECH MIYOTA CO., LTD. (4107-5, Oaza-Miyota Miyotamachi, Kitasaku-gu, Nagano 94, 〒3890294, JP)
International Classes:
G01C19/56
Attorney, Agent or Firm:
AOKI, Atsushi et al. (SEIWA PATENT & LAW, Toranomon 37 Mori Bldg. 5-1, Toranomon 3-chome, Minato-k, Tokyo 23, 〒1058423, JP)
Claims: