Seiko Epson Corporation

Epson Toyocom Corporation

Atsushi Kiyohara

Masayuki Ishikawa

Takehiro Yamamoto

Yosuke Itasaka

Kensaku Isohata

Norihito Matsukawa

Mihiro Nonoyama

Shinnosuke Kano

Shigenori Isozaki

Shigehisa Kurogo

A circuit device includes an A/D conversion circuit that performs A/D conversion on a temperature detection voltage from a temperature sensor so as to output temperature detection data, and a digital signal processing circuit that performs a temperature compensation process on the basis of the temperature detection data, in which the A/D conversion circuit operates in a first mode, and switches to a second mode in a case where a predetermined condition is established.

Circuit device, oscillator, electronic apparatus, vehicle, and manufacturing method for circuit device

An oscillation circuit includes a circuit for oscillation, a first frequency adjustment circuit for adjusting a frequency, and a first terminal. The oscillation circuit has a first mode in which the circuit for oscillation and the first frequency adjustment circuit are electrically connected to each other and the first frequency adjustment circuit and the first terminal are not electrically connected to each other, and a second mode in which the circuit for oscillation and the first frequency adjustment circuit operate and a terminal on a side where a signal of the first frequency adjustment circuit is output and the first terminal are electrically connected to each other.

Oscillation circuit, electronic apparatus, moving object, and method of adjusting oscillation circuit

An oscillation circuit includes a circuit for oscillation and a signal adjustment circuit connected to the circuit for oscillation. An input voltage based on a direct-current voltage, a voltage value of which can be changed, is input to the circuit for oscillation and the signal adjustment circuit. The circuit for oscillation causes a vibration piece to oscillate and outputs a first oscillation signal. A frequency of the first oscillation signal is adjusted according to the voltage value output from the signal adjustment circuit.

Oscillation circuit, oscillator, electronic apparatus, and moving object

An oscillator includes an oscillation element; an oscillation circuit which causes the oscillation element to oscillate; a heat generation element which heats the oscillation element; a temperature control circuit which controls the heat generation element; and a temperature correction circuit which corrects frequency-temperature characteristics of an output signal of the oscillation circuit.

Oscillator, electronic device and moving object

An oscillation circuit includes a circuit for frequency adjustment, a variable capacity control circuit in which a voltage to be output therefrom is controlled with either a voltage which is input from a terminal Tor a voltage other than the voltage which is input from the terminal T, a circuit for oscillation which is provided with a varactor and to which a signal from the circuit for frequency adjustment and a signal from the variable capacity control circuit are input, and a three-terminal switch which outputs the voltage which is input from the terminal Tto either the circuit for frequency adjustment or the variable capacity control circuit.

Oscillation circuit, oscillator, electronic device, mobile object, and oscillator manufacturing method

A voltage control type temperature compensation piezoelectric oscillator, includes: a voltage control type oscillation circuit; an automatic frequency control (AFC) circuit outputting a control voltage for controlling an oscillation frequency of the voltage control type oscillation circuit based on an external control voltage; a temperature compensation voltage generating circuit generating a temperature compensation voltage; and a gain variable circuit varying a gain of the temperature compensation voltage. In the oscillator, the gain variable circuit is controlled by the control voltage outputted from the AFC circuit, and the oscillation frequency of the voltage control type oscillation circuit is controlled by an output voltage of the gain variable circuit.

Voltage control type temperature compensation piezoelectric oscillator

An oscillator, includes an amplifier circuit including a semiconductor element having a first constant potential as reference potential for a power supply voltage, a variable capacitance element, a piezoelectric resonator, and a capacitance circuit constituting a closed circuit with the piezoelectric resonator. The amplifier circuit and the variable capacitance element are connected in series to provide a series circuit. The capacitance circuit connects the capacitance elements in a plurality of numbers in series. A connecting midpoint of the series connection is connected to a circuit for the first constant potential. Two connecting midpoints other than the midpoint of the closed circuit are used as connecting points to connect the series circuit and the closed circuit in parallel.

Oscillator

A voltage controlled oscillator controls an oscillation frequency based on a control voltage supplied from an external control voltage terminal. The voltage controlled oscillator includes a reference bias voltage circuit and a gain adjustment circuit. The reference bias voltage circuit includes multiple serial resistances between a reference voltage and a ground. The reference bias voltage circuit controls a switch coupled in parallel to at least one of the serial resistances and thus changes a voltage dividing ratio of the serial resistances so as to set a reference bias voltage. The gain adjustment circuit adjusts a gain of the control voltage. The gain adjustment circuit includes multiple resistances and multiple switching elements. The gain adjustment circuit controls the switching elements to form a voltage dividing circuit between the reference bias voltage and the external control voltage terminal so as to generate an automatic frequency control voltage.

Voltage controlled oscillator

A temperature-sensor circuit includes: a transistor having an emitter that is grounded, a collector, and a base; a first resistor having a first end and a second end, the first end being coupled with the collector; and a second resistor having a third end and a fourth end, the third end being coupled with the second end of the first resistor. A junction joining the first resistor and the second resistor is coupled with the base.

Temperature-sensor circuit, and temperature compensated piezoelectric oscillator

A temperature compensated piezoelectric oscillator includes: an oscillation circuit that drives a piezoelectric element with a current; a direct-current-stopping fixed capacitor; a frequency-temperature compensated circuit that compensates the deviation of an oscillation frequency caused by a change of temperature; and a piezoelectric transducer which includes a piezoelectric element driven in a prescribed frequency; where the above elements are connected serially.

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Chino, Japan

Atsushi Kiyohara