摘要:
A detection circuit includes a detection terminal to which an alternating current signal from a physical quantity transducer is input, a detection current/voltage conversion amplifier circuit that converts the alternating current signal input through the detection terminal into a voltage signal, an evaluation terminal that supplies an evaluation voltage signal to the detection current/voltage conversion amplifier circuit, an input resistor that has a given resistance ratio with respect to a feedback resistor; and a switch circuit of the detection circuit provided in a signal path that connects the evaluation terminal and an input node of the detection current/voltage conversion amplifier circuit.
摘要:
A driver device that forms an oscillation loop with a vibrator and causes the vibrator to produce driving vibrations includes a current-voltage converter that is provided in the oscillation loop and converts a current that flows through the vibrator into a voltage, and a GCA as a comparator that is provided in the oscillation loop and outputs a signal corresponding to a comparison result between an output from the current-voltage converter and a given voltage. The GCA outputs a first high-level voltage or a low-level voltage during oscillation startup, and outputs a second high-level voltage or the low-level voltage in a steady oscillation state. The first high-level voltage is a voltage higher in potential than the second high-level voltage.
摘要:
An oscillation driver circuit that drives a physical quantity transducer includes a one-input/two-output comparator. The one-input/two-output comparator includes a shared differential section that compares a voltage signal input from a drive current/voltage conversion amplifier circuit with a given voltage, a first output section that receives a signal output from the differential section, variably adjusts a voltage amplitude of the received signal, and outputs the resulting signal, and a second output section that receives the signal output from the differential section, and outputs a synchronous detection reference signal of which the voltage amplitude is fixed.
摘要:
A detection circuit includes a detection terminal to which an alternating current signal from a physical quantity transducer is input, a detection current/voltage conversion amplifier circuit that converts the alternating current signal input through the detection terminal into a voltage signal, an evaluation terminal that supplies an evaluation voltage signal to the detection current/voltage conversion amplifier circuit, an input resistor that has a given resistance ratio with respect to a feedback resistor; and a switch circuit of the detection circuit provided in a signal path that connects the evaluation terminal and an input node of the detection current/voltage conversion amplifier circuit.
摘要:
A driver device that forms an oscillation loop with a vibrator and causes the vibrator to produce driving vibrations includes a current-voltage converter that converts a current that flows through the vibrator into a voltage, an output circuit that causes the vibrator to produce the driving vibrations based on a signal that is converted into a voltage with respect to a given voltage, and a high-pass filter that is provided in the oscillation loop between the current-voltage converter and the output circuit. The driver device causes the vibrator to produce the driving vibrations while changing a reference potential of the high-pass filter, and then causes the vibrator to produce the driving vibrations while fixing the reference potential.
摘要:
An oscillation driver circuit includes a current-voltage converter which converts a current value of an oscillation signal in an oscillation loop into a voltage value, and a comparator which outputs a signal corresponding to the result of comparison between the output signal from the current-voltage converter and a given reference signal. The comparator has an output current limiting function. The oscillation driver circuit causes the vibrator to produce driving vibrations based on the output from the comparator.
摘要:
An oscillation driver circuit includes a gain control amplifier which causes a vibrator to produce driving vibrations by controlling an oscillation amplitude in an oscillation loop, and a comparator which generates a synchronous detection reference signal based on a signal in the oscillation loop. The oscillation driver circuit sets a gain in a first oscillation loop including the vibrator and the comparator to be larger than unity using an output from the comparator, and then causes the vibrator to produce the driving vibrations by controlling an oscillation amplitude in a second oscillation loop including the vibrator and the gain control amplifier in at least one of an oscillation startup state and a sleep mode.
摘要:
An oscillation driver circuit includes a current-voltage converter which converts a current value of an oscillation signal in an oscillation loop into a voltage value, and a comparator which outputs a signal corresponding to the result of comparison between the output signal from the current-voltage converter and a given reference signal. The comparator has an output current limiting function. The oscillation driver circuit causes the vibrator to produce driving vibrations based on the output from the comparator.
摘要:
A driver device includes a gain control amplifier that causes a vibrator to produce driving vibrations by controlling an oscillation amplitude in an oscillation loop, a signal generation circuit that generates a signal having a given frequency, and a modulation circuit that modulates the frequency of the signal generated by the signal generation circuit to a resonance frequency of the vibrator. The driver device causes the vibrator to produce the driving vibrations using the signal modulated by the modulation circuit, and then causes the vibrator to produce the driving vibrations by controlling the oscillation amplitude in the oscillation loop formed by the vibrator and the gain control amplifier.
摘要:
An oscillation driver circuit includes a gain control amplifier which causes a vibrator to produce driving vibrations by controlling an oscillation amplitude in an oscillation loop, and a comparator which generates a synchronous detection reference signal based on a signal in the oscillation loop. The comparator has an output current limiting function. The oscillation driver circuit causes the vibrator to produce vibrations using an output from the comparator in a state in which the gain in an oscillation loop formed by the vibrator and the comparator is set to be larger than unity, and then causes the vibrator to produce the driving vibrations by controlling an oscillation amplitude in an oscillation loop formed by the vibrator and the gain control amplifier.