Detection device, sensor, electronic apparatus, and moving object

Patent metadata

Field	Value
Publication number	US-9506758-B2
Application number	US-201414217581-A
Country	US
Kind code	B2
Filing date	Mar 18, 2014
Priority date	Mar 22, 2013
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

A detection device includes a driving circuit that drives a vibrator, and a detection circuit that receives a detection signal from the vibrator and performs a detection process of detecting a physical quantity signal corresponding to a physical quantity from the detection signal. The driving circuit performs intermittent driving in which the vibrator is driven in a driving period, and is not driven in a non-driving period, and the detection circuit performs the detection process of the physical quantity signal in the non-driving period of the intermittent driving.

First claim

What is claimed is:

1. A detection device comprising:
a driving circuit that drives a vibrator; and
a detection circuit that receives a detection signal from the vibrator and performs a detection process of detecting a physical quantity signal corresponding to a physical quantity from the detection signal,
wherein the driving circuit performs intermittent driving in which the vibrator is driven in a driving period, and is not driven in a non-driving period,
wherein the detection circuit performs the detection process of the physical quantity signal in the non-driving period of the intermittent driving, and
wherein the driving circuit performs the intermittent driving in which the driving period and the non-driving period of the vibrator are alternately repeated.

2. The detection device according to claim 1 ,
wherein the driving circuit includes a driving signal output circuit that outputs a driving signal to the vibrator, and
wherein the driving signal output circuit includes at least one of a circuit that outputs a fixed voltage and a circuit that sets an output node of the driving signal output circuit to a high impedance state, in the non-driving period.

3. The detection device according to claim 2 ,
wherein the driving signal output circuit outputs the driving signal of a rectangular wave in the driving period of the vibrator.

4. The detection device according to claim 1 ,
wherein the detection circuit includes at least one of a synchronous detection circuit that performs synchronous detection and an A/D conversion circuit that performs A/D conversion on the detection signal, and
wherein at least one of a synchronous detection operation of the synchronous detection circuit and an A/D conversion operation of the A/D conversion circuit is stopped in the driving period.

5. The detection device according to claim 1 ,
wherein the driving circuit includes
an amplification circuit that amplifies the detection signal from the vibrator; and
a gain control circuit that performs gain control on the basis of an output signal of the amplification circuit, and
wherein, in the non-driving period, an operation of the amplification circuit is not stopped, and operations of at least some circuits of the gain control circuit are stopped.

6. The detection device according to claim 1 ,
wherein the detection circuit includes a low-pass filter having a frequency characteristic which allows a physical quantity signal corresponding to the physical quantity to pass through the low-pass filter so as to attenuate an unnecessary signal, and
wherein, when a cutoff frequency of the low-pass filter is fc, lengths of the driving period and the non-driving period are respectively T 1 and T 2 , a relationship of 1/(T 1 +T 2 )>fc is satisfied.

7. The detection device according to claim 1 ,
wherein the detection circuit does not perform the detection process of the physical quantity signal in the driving period, and performs the detection process of the physical quantity signal in the non-driving period.

8. The detection device according to claim 1 , further comprising:
a mode switching register that sets switching between an intermittent driving mode in which the intermittent driving is performed and a normal driving mode in which continuous driving is performed.

9. The detection device according to claim 1 , further comprising:
a period setting register that sets lengths of the driving period and the non-driving period.

10. A detection device comprising:
a driving circuit that drives a vibrator; and
a detection circuit that receives a detection signal from the vibrator and performs a detection process of detecting a physical quantity signal corresponding to a physical quantity from the detection signal,
wherein the driving circuit performs intermittent driving in which a driving period and a non-driving period of the vibrator are alternately repeated,
wherein the driving circuit includes a driving signal output circuit that outputs a driving signal to the vibrator, and
wherein the driving signal output circuit includes at least one of a circuit that outputs a fixed voltage and a circuit that sets an output node of the driving signal output circuit to a high impedance state to output at least one of the fixed voltage and the high impedance during the non-driving period of the intermittent driving.

11. The detection device according to claim 1 ,
wherein the detection circuit includes
a first current-voltage conversion circuit to which a first detection signal is input;
a second current-voltage conversion circuit to which a second detection signal is input;
a first gain adjustment amplifier that amplifies an output signal of the first current-voltage conversion circuit through adjustment of a gain;
a second gain adjustment amplifier that amplifies an output signal of the second current-voltage conversion circuit through adjustment of a gain;
a switching mixer that has a first input node to which an output signal from the first gain adjustment amplifier is input and a second input node to which an output signal from the second gain adjustment amplifier is input, performs synchronous detection on the output signal of the first gain adjustment amplifier and the output signal of the second gain adjustment amplifier which are differential signals on the basis of a synchronization signal from the driving circuit, outputs a first output signal to a first output node and outputs a second output signal to a second output node, wherein the first output signal and the second output signal are differential signals;
a first filter to which the first output signal from the first output node of the switching mixer is input;
a second filter to which the second output signal from the second output node of the switching mixer is input; and
an A/D conversion circuit that receives an output signal from the first filter and an output signal from the second filter and performs differential A/D conversion thereon.

12. The detection device according to claim 10 ,
wherein the detection circuit includes
a first current-voltage conversion circuit to which a first detection signal is input;
a second current-voltage conversion circuit to which a second detection signal is input;
a first gain adjustment amplifier that amplifies an output signal of the first current-voltage conversion circuit through adjustment of a gain;
a second gain adjustment amplifier that amplifies an output signal of the second current-voltage conversion circuit through adjustment of a gain;
a switching mixer that has a first input node to which an output signal from the first gain adjustment amplifier is input and a second input node to which an output signal from the second gain adjustment amplifier is input, performs synchronous detection on the output signal of the first gain adjustment amplifier and the output signal of the second gain adjustment amplifier which are differential signals on the basis of a synchronization signal from the driving circuit, outputs a first output signal to a first output node and outputs a second output signal to a second output node, wherein the first output signal and the second output signal are differential signals;
a first filter to which the first output signal from the first output node of the switching mixer is input;
a second filter to which the second output signal from the second output node of the switching mixer is input; and
an A/D conversion circuit that receives an output signal from the first filter and an output signal from the second filter and performs differential A/D conversion thereon.

13. A sensor comprising:
the detection d

Assignees

• Seiko Epson Corp

Inventors

• Maki Katsuhiko
• Nomiya Takashi

Classifications

• G01C19/5726

  Signal processing · CPC title

• G01C19/5776 Primary

  Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719 · CPC title

• G01C19/5762

  the sensing mass being connected to a driving mass, e.g. driving frames · CPC title

• G01C19/5614

  Signal processing · CPC title