PHYSICAL-QUANTITY DETECTION CIRCUIT, PHYSICAL-QUANTITY SENSOR, AND ELECTRONIC DEVICE

摘要

A physical-quantity sensor is configured to be used with a physical-quantity sensor element that outputs a sensor signal in response to a physical quantity. A physical-quantity detection circuit of the physical-quantity sensor includes a signal generating unit for generating a detecting signal and a multiplier that multiplies the sensor signal by the detecting signal. The signal generating unit converts a first phase of a predetermined signal having a frequency corresponding to a frequency of the sensor signal, into a second phase, and calculates an amplitude value corresponding to the second phase as to generate the detecting signal. This physical-quantity sensor improves accuracy of phase adjustment without increasing a sampling frequency.

主权项

1. A physical-quantity detection circuit to be used with a physical-quantity sensor element that outputs a sensor signal in response to a physical quantity, the physical-quantity detection circuit comprising:
a signal generating unit for generating a detecting signal; and a multiplier for multiplying the sensor signal by the detecting signal, wherein the signal generating unit is configured to:
generate a predetermined signal having a frequency corresponding to a frequency of the sensor signal;convert a first phase of the predetermined signal into a second phase; andcalculate an amplitude value corresponding to the second phase as to generate the detecting signal, and wherein a waveform of the detecting signal is a sinewave.