An integrated circuit device includes an oscillation circuit that generates an oscillation signal by causing a resonator to oscillate, a temperature compensation circuit that performs temperature compensation of an oscillation frequency of the oscillation circuit, an output circuit that outputs a clock signal based on the oscillation signal, a first regulator that generates a first regulated power supply voltage based on a power supply voltage and supplies the first regulated power supply voltage to the temperature compensation circuit, and a second regulator that generates a second regulated power supply voltage based on the power supply voltage and supplies the second regulated power supply voltage to the output circuit.

An integrated circuit device includes a first pad and a second pad electrically coupled to one end and the other end of a resonator, an oscillation circuit that is electrically coupled to the first pad and the second pad and generates an oscillation signal by causing the resonator to oscillate, and an output circuit that outputs a clock signal based on the oscillation signal. The oscillation circuit is disposed along a first side of the integrated circuit device among the first side, a second side that intersects the first side, a third side that is an opposite side of the first side, and a fourth side that is an opposite side of the second side. The first pad and the second pad are disposed in the oscillation circuit along the first side in a plan view, and the output circuit is disposed along the second side.

Provided is a circuit device including: a first terminal electrically coupled to one end of a vibrator; a second terminal electrically coupled to the other end of the vibrator; a first coupling wiring electrically coupled to the first terminal; a second coupling wiring electrically coupled to the second terminal; an oscillation circuit having a drive circuit for driving the vibrator via the first coupling wiring and the second coupling wiring, and oscillating the vibrator; and a first capacitor having a metal-insulator-metal (MIM) structure of which one electrode is electrically coupled to the first coupling wiring. The first coupling wiring and the first capacitor having the MIM structure overlap each other in plan view in a direction orthogonal to a substrate on which a circuit element is formed.

Provided is a circuit device including: an oscillation circuit oscillating a vibrator, in which the oscillation circuit includes a variable capacitance circuit having a first variable capacitance element and a second variable capacitance element constituted by a first transistor and a second transistor, and a reference voltage supply circuit. The first reference voltage is supplied to a first gate of the first transistor and a capacitance control voltage is supplied to a first impurity region of the first transistor, the second reference voltage is supplied to a second gate of the second transistor and the capacitance control voltage is supplied to a second impurity region of the second transistor, and the capacitance control voltage is supplied to a first common impurity region of the first transistor and the second transistor.

Provided is a circuit device including: a first terminal electrically coupled to one end of a vibrator; a second terminal electrically coupled to the other end of the vibrator; an oscillation circuit electrically coupled to the first terminal and the second terminal, and oscillating the vibrator; a third terminal to which an external input signal is input; a switch circuit provided between a first wiring which couples the first terminal and the oscillation circuit with each other and the third terminal, and having a P-type transistor; and a control circuit outputting a regulated voltage, in which a power supply voltage is regulated, as a substrate voltage of the P-type transistor.

A circuit device includes a control voltage input terminal to which a control voltage is inputted, an A/D conversion circuit A/D-converting the control voltage to generate control voltage data and A/D-converting a temperature detection voltage from a temperature sensor to generate temperature detection data, a processing circuit generating temperature compensation data of an oscillation frequency based on the temperature detection data and performing addition processing of the temperature compensation data and the control voltage data to generate frequency control data of the oscillation frequency, and an oscillation signal generation circuit generating an oscillation signal of the oscillation frequency set by the frequency control data, using the frequency control data and a resonator.

An oscillator includes: an external terminal, a resonator, and an oscillation circuit that oscillates the resonator, in which the oscillation circuit includes an amplification circuit and a current source which supplies a current to the amplification circuit, in which the current is set according to a first control signal which is input from the external terminal and a drive level of the resonator is changed according to the setting of the current.

An oscillator includes a resonator and an integrated circuit, the integrated circuit includes an oscillation circuit that oscillates the resonator, a temperature sensor, a temperature compensation circuit that compensates for temperature characteristics of the resonator based on an output signal of the temperature sensor, an output circuit that receives a signal output from the oscillation circuit and outputs an oscillation signal, and a heat generating circuit, and in the heat generating circuit, a current flows in a first period after supply of a power supply voltage from the outside is started to generate heat and no current flows in the second period after the first period ends.

An oscillation circuit includes a first node, a first switching element, and a second switching element and has a first mode in which the first switching element does not electrically couple the first external connection terminal and the first node and the second switching element does not electrically couple the first node and the second external connection terminal which is electrically coupled to one end of a resonator and a second mode in which the first switching element electrically couples the first external connection terminal and the first node and the second switching element electrically couples the first node and the second external connection terminal, and in the first mode, a voltage of the first node is fixed.

A crystal driving circuit comprising a circuit input node and a circuit output node, a high power amplifier having a power consumption of more than 100 W, a low power amplifier comprising a power consumption less than 10 W, the circuit being arranged to selectively isolate the high power amplifier and associated load capacitance from the circuit input node and the circuit output node.