Abstract: A resonance frequency detector has an adder that adds a correction term to an oscillation frequency of an output signal of an oscillator, and detects a predetermined resonance frequency of a resonance element. The correction term is generated based on a phase error in a phase locked loop and a degree of change in phase at the resonance frequency, and the phase locked loop generates a control signal based on the phase error between an output signal of the resonance element that resonates at the resonance frequency and the output signal of the oscillator that varies the oscillation frequency according to the control signal.

Abstract: An amplifier circuit includes a plurality of gain stages that change a gain in each stage and include a first gain stage and a final gain stage, an output terminal that outputs a signal amplified by the plurality of gain stages, a negative input terminal connected to an input node of the first gain stage, a feedback circuit connected between an output node of the final gain stage and the negative input terminal, a first resistor connected between the output node of the final gain stage and the output terminal, an active load of the first gain stage including a first transistor, a second resistor connected to a gate or a base of the first transistor, and a capacitor connected between the gate or the base of the first transistor and the output node of the final gain stage.

Abstract: A resonance frequency detector has an adder that adds a correction term to an oscillation frequency of an output signal of an oscillator, and detects a predetermined resonance frequency of a resonance element. The correction term is generated based on a phase error in a phase locked loop and a degree of change in phase at the resonance frequency, and the phase locked loop generates a control signal based on the phase error between an output signal of the resonance element that resonates at the resonance frequency and the output signal of the oscillator that varies the oscillation frequency according to the control signal.

Abstract: A protection circuit comprises a first transistor, a comparator, a second transistor, and a third transistor. The first transistor has a gate connected to an input terminal and configured to pass a drain current based on a potential at the input terminal. The comparator has a non-inverting terminal to which a source of the first transistor is connected and an inverting terminal to which a reference voltage is applied. The second transistor has a gate to which an output of the comparator is applied, a source connected to a power supply voltage, and a drain connected to the input terminal. The third transistor has a gate to which a predetermined voltage is applied, a drain connected to the gate of the second transistor, and a source connected to the drain of the input transistor.

Abstract: A phase locked loop has an oscillator that varies a frequency according to a control signal, a resonance element that resonates at a predetermined resonance frequency and output a signal obtained by shifting a phase of an output signal of the oscillator by 90 degrees at the resonance frequency, a phase detector that detects a phase error between an output signal of the resonance element and an output signal of the oscillator, a feedback controller that controls a frequency of an output signal of the oscillator by proportional control and integral control according to the phase error, and a control signal corrector that corrects the control signal by adding a correction term corresponding to environment information to an output signal of the feedback controller.

Abstract: A protection circuit comprises a first transistor, a comparator, a second transistor, and a third transistor. The first transistor has a gate connected to an input terminal and configured to pass a drain current based on a potential at the input terminal. The comparator has a non-inverting terminal to which a source of the first transistor is connected and an inverting terminal to which a reference voltage is applied. The second transistor has a gate to which an output of the comparator is applied, a source connected to a power supply voltage, and a drain connected to the input terminal. The third transistor has a gate to which a predetermined voltage is applied, a drain connected to the gate of the second transistor, and a source connected to the drain of the input transistor.

Abstract: According to one embodiment, a detector is disclosed. The detector has a mechanism with first and second vibrators which vibrate in first and second directions. Circuits detect output first and second signals conforming to the detected positions of the vibrators. A detection circuit detects second signal using the first signal as a reference of synchronous detection and outputs a detection signal. A filter continues a moving average process on the detection signal for a period set based on the first signal. A controller circuitry controls the mechanism to causes the first vibrator to start vibrating in the first direction in synchronization with a clock signal.

Abstract: According to one embodiment, a method for controlling a vibration device includes a movable body capable of vibrating in a first direction, and a catch and release mechanism capable of catching the movable body that freely vibrates in the first direction, by an electrostatic attractive force, and releasing the caught movable body to freely vibrate the movable body in the first direction, wherein in a condition that tc is a time from a rise start time point to a rise end time point of an applied voltage for catching the movable body that freely vibrates in the first direction, by the electrostatic attractive force, and td is a period of the free vibration in the first direction of the movable body, the time tc is longer than the time td.

Abstract: According to one embodiment, a detector is disclosed. The detector has a mechanism with first and second vibrators which vibrate in first and second directions. Circuits detect output first and second signals conforming to the detected positions of the vibrators. A detection circuit detects second signal using the first signal as a reference of synchronous detection and outputs a detection signal. A filter continues a moving average process on the detection signal for a period set based on the first signal. A controller circuitry controls the mechanism to causes the first vibrator to start vibrating in the first direction in synchronization with a clock signal.

Abstract: A system has receiver circuitry configured to receive mirror information including at least one of a position, size, height, or an angle of the mirror and surrounding information acquired by measurement of at least part of surrounding of the mirror, and processing circuitry configured to specify a first range observable via a reflection in the mirror, estimate, based on the surrounding information, a second range observable via a reflection in the mirror whose at least one of the position, size, height, or angle is changed, and generate adjustment information used to adjust at least one of the position, height, or angle of the mirror in accordance with the first range information and the second range information.

Abstract: A detection device detects a dynamic quantity exerted on a detection mechanical system including first and second mechanical oscillators. The detection device includes first to third transducers, a canceller, a low-pass filter, and an inverting amplification unit. The first transducer detects the first mechanical oscillator position in a first direction to output a first signal. The second transducer detects the second mechanical oscillator position in a second direction to output a second signal. The canceller inverts a direction in which a signal detected by the second transducer from the second mechanical oscillator varies according to the first signal. The third transducer detects the second mechanical oscillator position in the second direction to output a third signal. The inverting amplification unit gives a control signal generated by inverting the third signal to a second actuator moving the second mechanical oscillator.

Abstract: According to one embodiment, a vibration apparatus includes a coupled vibration mechanism which includes a plurality of mass parts and connects the mass parts, a catch and release mechanism which catches a vibrating mass parts to stop vibration and releases a caught mass parts to start vibration and a control circuitry configured to determine whether catching the mass parts by the catch and release mechanism is successful or failed and control the catch and release mechanism for raising possibility for catching the mass parts by the catch and release mechanism, if the catching the mass parts is determined as failed.

Abstract: According to one embodiment, a vibration device is disclosed. The device includes a mass unit including a mass unit, a catch and release mechanism to catch and release the mass unit and including an electrode unit, and a control unit to control catching and releasing of the mass unit by a voltage to be applied between the mass unit and the electrode unit. The control unit controls the voltage such that a voltage greater than a steady voltage is to be applied between the mass and electrode units before the steady voltage is applied between the mass and electrode units. The voltage greater than the steady voltage is to be applied in at least part of a period during which the mass unit is vibrating after the mass unit is released from the catch and release mechanism.

Abstract: According to one embodiment, a voltage-current conversion circuit includes an amplifier first, second and third inputs, a transistor including a first and second terminals, and a control terminal electrically connected to an output of the amplifier, and a serial connection including resistors connected in series between the first terminal and an ac ground, wherein a predetermined connecting point, among a first connecting point between the first terminal and the serial connection, a second connecting point between the ac ground and the serial connection, and one or more third connecting points between the resistors, is connected to the second input, and one of the connecting points other than the predetermined connecting point is connected to the third input.

Abstract: An analog-to-digital converter has a switched capacitor comprising a capacitor to perform charging and discharging by switching a switch, the switched capacitor varying a charge amount of the capacitor in accordance with a frequency of an oscillation signal in accordance with a differential signal between an input signal and a feedback signal, capacitance of the capacitor, and a predetermined bias voltage, a feedback signal generator to generate the feedback signal based on an output signal of the switched capacitor, and a digital converter to generate a digital signal by digital conversion of the input signal based on the oscillation signal.

Abstract: According to one embodiment, a vibration apparatus includes a coupled vibration mechanism which includes a plurality of mass parts and connects the mass parts, a catch and release mechanism which catches a vibrating mass parts to stop vibration and releases a caught mass parts to start vibration and a control circuitry configured to determine whether catching the mass parts by the catch and release mechanism is successful or failed and control the catch and release mechanism for raising possibility for catching the mass parts by the catch and release mechanism, if the catching the mass parts is determined as failed.

Abstract: According to one embodiment, a voltage-current conversion circuit includes an amplifier first, second and third inputs, a transistor including a first and second terminals, and a control terminal electrically connected to an output of the amplifier, and a serial connection including resistors connected in series between the first terminal and an ac ground, wherein a predetermined connecting point, among a first connecting point between the first terminal and the serial connection, a second connecting point between the ac ground and the serial connection, and one or more third connecting points between the resistors, is connected to the second input, and one of the connecting points other than the predetermined connecting point is connected to the third input.

Abstract: According to one embodiment, a detector is disclosed. The detector has a mechanism with first and second vibrators which vibrate in first and second directions. Circuits detect output first and second signals conforming to the detected positions of the vibrators. A detection circuit detects second signal using the first signal as a reference of synchronous detection and outputs a detection signal. A filter continues a moving average process on the detection signal for a period set based on the first signal. A controller circuitry controls the mechanism to causes the first vibrator to start vibrating in the first direction in synchronization with a clock signal.

Abstract: Amplifier circuitry has sampling circuitry which samples an input voltage, a quantizer which quantizes an output voltage of the sampling circuitry and outputs an output code, a differential amplifier which amplifies a differential voltage between the output voltage of the sampling circuitry and a reference voltage and performs offset adjustment according to the output code of the quantizer, and a first capacitor which is connected between an output node of the differential amplifier and an output node of the sampling circuitry.

Abstract: According to one embodiment, a method for controlling a vibration device includes a movable body capable of vibrating in a first direction, and a catch and release mechanism capable of catching the movable body that freely vibrates in the first direction, by an electrostatic attractive force, and releasing the caught movable body to freely vibrate the movable body in the first direction, wherein in a condition that tc is a time from a rise start time point to a rise end time point of an applied voltage for catching the movable body that freely vibrates in the first direction, by the electrostatic attractive force, and td is a period of the free vibration in the first direction of the movable body, the time tc is longer than the time td.