Patent ID: 8381595
Filing Date: 2013-02-26
Classification: G01L

Abstract:
1. A pressure detecting device comprising: a resonator whose oscillation frequency varies depending on a pressure; a first oscillation circuit that oscillates the resonator and outputs a signal of a frequency corresponding to the pressure; an AT-cut quartz crystal resonator; a second oscillation circuit that oscillates the AT-cut quartz crystal resonator and outputs a reference clock signal; a measuring unit that measures the reference clock signal in a gate period based on the period of the signal output from the first oscillation circuit by the use of a reciprocal counting method; a temperature detecting unit that detects a temperature of the resonator or around the resonator; and a storage unit that stores coefficients of a first approximating polynomial for calculating a first correction value used to compensate for a frequency-temperature characteristic of the measuring unit, wherein the frequency-temperature characteristic of the value measured by the measuring unit includes a frequency-temperature characteristic of the AT-cut quartz crystal resonator and a frequency-temperature characteristic of the resonator.