Temperature-compensated oscillator and electronic device

• US 8,669,825 B2
• Filed: 04/13/2012
• Issued: 03/11/2014
• Est. Priority Date: 04/18/2011
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Terasawa, Katsuyoshi
• Primary Examiner(s): Gannon, Levi
• Application Number:
  US13/446,245
• Publication Number:
  US 20120262244A1
• Time in Patent Office: 697 Days
• Field of Search: 310/315, 310/346, 331/154, 331/156, 331/158, 331/176, 331/186
• US Class Current: 331/176
• CPC Class Codes: H03L 1/022 by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature H03L1/021 takes precedence

Abstract

A temperature-compensated oscillator includes a temperature compensation circuit adapted to output a temperature compensation voltage, a voltage-controlled oscillation circuit on which temperature compensation is performed based on the temperature compensation voltage, a switch circuit adapted to perform ON/OFF control on power supply to the temperature compensation circuit, and a sample-and-hold circuit adapted to perform switching control between an ON state of outputting the temperature compensation voltage to the voltage-controlled oscillation circuit while being connected to the temperature compensation circuit and holding the temperature compensation voltage output from the temperature compensation circuit when the power is supplied to the temperature compensation circuit, and an OFF state of outputting the temperature compensation voltage held to the voltage-controlled oscillation circuit while cutting connection to the temperature compensation circuit when the power supply to the temperature compensation circuit is cut.

Claims

1. A temperature-compensated oscillator comprising:

a voltage-controlled oscillation circuit;

a temperature compensation circuit adapted to output a temperature compensation voltage used for temperature compensation of an oscillation frequency of the voltage-controlled oscillation circuit;

a switch circuit adapted to perform ON/OFF control on power supply to the temperature compensation circuit;

a sample-and-hold circuit adapted to perform switching control between

an ON state of outputting the temperature compensation voltage output from the temperature compensation circuit to the voltage-controlled oscillation circuit while holding the temperature compensation voltage when the power is supplied to the temperature compensation circuit, and

an OFF state of outputting the temperature compensation voltage held to the voltage-controlled oscillation circuit while cutting connection to the temperature compensation circuit when the power supply to the temperature compensation circuit is cut; and

an output circuit adapted to output an ON/OFF signal for performing switching control between an ON state and an OFF state of the switch circuit, and output an ON/OFF signal for performing the switching control of the sample-and-hold circuit, the output circuit includes an LC oscillation circuit as an oscillation source circuit of the ON/OFF signals.

2. The temperature-compensated oscillator according to claim 1, wherein,

the output circuit includes

an integration circuit adapted to integrate an oscillation signal from the oscillation source circuit, and

a comparator adapted to output a signal representing a magnitude relation between a voltage of a signal integrated and a threshold voltage to each of the switch circuit side and the sample-and-hold circuit side as the ON/OFF signal.

3. The temperature-compensated oscillator according to claim 2, wherein

the output circuit includes

a voltage control section adapted to control the threshold voltage.

4. The temperature-compensated oscillator according to claim 2, wherein

the output circuit includes

a delay circuit to which an output signal of the comparator is input, and which outputs a delay signal obtained by delaying a voltage variation in the output signal of the comparator,

an OR circuit adapted to output a signal representing an OR result between the ON/OFF signal and the delay signal to the switch circuit as the ON/OFF signal, and

an AND circuit adapted to output a signal representing an AND result between the output signal of the comparator and the delay signal to the sample-and-circuit as the ON/OFF signal.

5. The temperature-compensated oscillator according to claim 1, further comprising:

a low-pass filter disposed at least one of

between the temperature compensation circuit and the sample-and-hold circuit, and

between the sample-and-hold circuit and the voltage-controlled oscillation circuit.

6. An electronic device comprising:

the temperature-compensated oscillator according to claim 1.

7. A temperature-compensated oscillator comprising:

a voltage-controlled oscillation circuit;

a temperature compensation circuit adapted to output a temperature compensation voltage used for temperature compensation of an oscillation frequency of the voltage-controlled oscillation circuit;

a switch circuit adapted to perform ON/OFF control on power supply to the temperature compensation circuit;

a sample-and-hold circuit adapted to perform switching control between

an ON state of outputting the temperature compensation voltage output from the temperature compensation circuit to the voltage-controlled oscillation circuit while holding the temperature compensation voltage when the power is supplied to the temperature compensation circuit, and

an OFF state of outputting the temperature compensation voltage held to the voltage-controlled oscillation circuit while cutting connection to the temperature compensation circuit when the power supply to the temperature compensation circuit is cut; and

wherein

an oscillation source circuit of the ON/OFF signal of the output circuit is the voltage-controlled oscillation circuit.

8. An electronic device comprising:

the temperature-compensated oscillator according to claim 7.