Circuit device, electronic apparatus, moving object and method of manufacturing of physical quantity detection device

Patent metadata

Field	Value
Publication number	US-10072929-B2
Application number	US-201614996524-A
Country	US
Kind code	B2
Filing date	Jan 15, 2016
Priority date	Jan 22, 2015
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

A circuit device includes a clock signal generation circuit that generates a clock signal through an oscillation circuit, and a detection circuit including a circuit operating through an operation signal based on the clock signal. The clock signal generation circuit includes a first frequency adjustment unit which is capable of adjusting an oscillation frequency before an physical quantity transducer and the circuit device are connected to each other, and a second frequency adjustment unit which is capable of adjusting the oscillation frequency in a state where the physical quantity transducer and the circuit device are connected to each other.

First claim

What is claimed is:

1. A circuit device comprising:
a clock signal generation circuit, including an oscillation circuit, which generates a clock signal through the oscillation circuit; and
a detection circuit, including a circuit operating through an operation signal based on the clock signal, to which a detection signal from a physical quantity transducer is input,
wherein the clock signal generation circuit includes
a first frequency adjustment circuit configured to adjust an oscillation frequency of the oscillation circuit before the physical quantity transducer and the circuit device are connected to each other, and
a second frequency adjustment circuit configured to adjust the oscillation frequency of the oscillation circuit in a state where the physical quantity transducer and the circuit device are connected to each other.

2. The circuit device according to claim 1 ,
wherein the oscillation circuit is a CR oscillation circuit, and
the first frequency adjustment circuit is a variable resistance circuit of the CR oscillation circuit.

3. The circuit device according to claim 2 ,
wherein the CR oscillation circuit includes an amplifier circuit, and
the variable resistance circuit is a resistance circuit that feeds back a signal of the amplifier circuit to an input node of the amplifier circuit.

4. The circuit device according to claim 3 ,
wherein the variable resistance circuit includes
a plurality of resistive elements which are connected in series to each other, and
a plurality of fuse elements in which each fuse element is provided in parallel to each resistive element of the plurality of resistive elements.

5. The circuit device according to claim 2 ,
wherein the variable resistance circuit includes
a plurality of resistive elements which are connected in series to each other, and
a plurality of fuse elements in which each fuse element is provided in parallel to each resistive element of the plurality of resistive elements.

6. The circuit device according to claim 5 ,
wherein the variable resistance circuit includes
a reference resistive element which is connected in series to the plurality of resistive elements, and
a trimming auxiliary switch, provided in parallel to the reference resistive element, which is turned off in a first measurement mode of the oscillation frequency before fuse cut, and is turned on in a second measurement mode of the oscillation frequency before the fuse cut.

7. The circuit device according to claim 1 ,
wherein the oscillation circuit is a CR oscillation circuit, and
the second frequency adjustment circuit is a variable capacitance circuit of the CR oscillation circuit.

8. The circuit device according to claim 7 ,
wherein the CR oscillation circuit includes an amplifier circuit, and
the variable capacitance circuit is provided to an output node of the amplifier circuit.

9. The circuit device according to claim 1 , further comprising:
a voltage generation circuit that generates a power supply voltage, and supplies the power supply voltage to the oscillation circuit,
wherein the voltage generation circuit generates a power supply voltage for compensating for temperature characteristics of the oscillation frequency of the oscillation circuit.

10. The circuit device according to claim 9 ,
wherein the oscillation frequency in a case where the power supply voltage is a fixed voltage has positive temperature characteristics, and
the voltage generation circuit generates the power supply voltage having negative temperature characteristics on the basis of a work function difference of a transistor, and supplies the power supply voltage as a power supply of the oscillation circuit.

11. The circuit device according to claim 10 ,
wherein the voltage generation circuit supplies a first voltage as the power supply voltage when the physical quantity transducer which is connected to the circuit device is a first physical quantity transducer, and
supplies a second voltage different from the first voltage as the power supply voltage when the physical quantity transducer which is connected to the circuit device is a second physical quantity transducer having a drive frequency different from that of the first physical quantity transducer.

12. The circuit device according to claim 9 ,
wherein the voltage generation circuit supplies a first voltage as the power supply voltage when the physical quantity transducer which is connected to the circuit device is a first physical quantity transducer, and
supplies a second voltage different from the first voltage as the power supply voltage when the physical quantity transducer which is connected to the circuit device is a second physical quantity transducer having a drive frequency different from that of the first physical quantity transducer.

13. The circuit device according to claim 1 ,
wherein the detection circuit includes an A/D conversion circuit that performs a sampling operation of an input signal on the basis of a sampling clock signal which is the operation signal.

14. The circuit device according to claim 1 ,
wherein the detection circuit includes a digital signal processing unit that performs digital signal processing on the basis of an operation clock signal which is the operation signal.

15. The circuit device according to claim 1 , further comprising:
a drive circuit that receives a feedback signal from the physical quantity transducer, and drives the physical quantity transducer.

16. The circuit device according to claim 15 ,
wherein when the oscillation frequency of the oscillation circuit is set to fos, i is set to an integer of 1 or greater, j is set to an integer of 1 or greater, and a frequency of the operation signal is set to fos/i, the oscillation frequency fos is set so that a relation of j×fdr≠fos/i is established, and wherein fdr corresponds to a drive frequency of the physical quantify transducer.

17. The circuit device according to claim 16 ,
wherein when k is set to an integer of 1 or greater, the oscillation frequency fos is set so that a relation of j×fdr≠k×fos/i is established.

18. An electronic apparatus comprising the circuit device according to claim 1 .

19. A moving object comprising the circuit device according to claim 1 .

20. A method of manufacturing a physical quantity detection device including a physical quantity transducer and a circuit device, the method comprising:
manufacturing a circuit device that includes a clock signal generation circuit, including an oscillation circuit, which generates a clock signal through the oscillation circuit, and a detection circuit, including a circuit operating through an operation signal based on the clock signal, to which a detection signal from the physical quantity transducer is input;
firstly adjusting an oscillation frequency of the oscillation circuit before the physical quantity transducer and the circuit device are connected to each other; and
secondly adjusting the oscillation frequency of the oscillation circuit in a state where the physical quantity transducer and the circuit device are connected to each other.

Assignees

• Seiko Epson Corp

Inventors

• Higuchi Teppei
• Maki Katsuhiko

Classifications

• G01C19/5628

  Manufacturing; Trimming; Mounting; Housings · CPC title

• G01C19/5649

  Signal processing · CPC title

• H03B5/04

  Modifications of generator to compensate for variations in physical values, e.g. power supply, load, temperature · CPC title

• G01C19/5614 Primary

  Signal processing · CPC title