Seiko Epson Corporation

Seiko Npc Corporation

Toshihiro Nishida

Takayuki Kikuchi

Masahiro Oshio

Yoshinao Yanagisawa

Masayuki Takahashi

A signal processing circuit includes an I/V conversion circuit (current/voltage conversion section) that converts an oscillation current of a vibrator into a voltage, an RC filter (phase shift section) that shifts a phase of the output signal of the I/V conversion circuit, a full-wave rectifier (part of a drive amplitude control section) that binarizes a signal that has been shifted in phase to generate a switch control signal, a comparator (reference signal generation section) that generates a reference signal for synchronous detection based on the output signal of the I/V conversion circuit, and an EXOR circuit (clock signal generation section) that generates a clock signal for a switched capacitor filter (SCF) that has a frequency twice a frequency of a drive signal based on a phase difference between the reference signal and the switch control signal.

Signal processing circuit, physical quantity detection apparatus, angular velocity detection apparatus, integrated circuit device, and electronic instrument

A detection circuit includes a synchronous detection circuit (synchronous detection section) that synchronously detects a signal that includes a detection signal of a vibrator (an output signal of an amplifier), a switched capacitor filter (SCF) circuit that filters a signal that has been synchronously detected by the synchronous detection circuit (an output signal of a programmable gain amplifier), and an output buffer that buffers and outputs a signal that has been filtered by the SCF circuit, the gain of the SCF circuit being larger than 1.

Detection circuit, physical quantity detection apparatus, angular velocity detection apparatus, integrated circuit device, and electronic instrument

A driver circuit includes a comparator (drive signal generation section) that generates a drive signal based on a signal obtained by converting an oscillation current of a vibrator that has been input via a first signal line into a voltage using an I/V conversion circuit (current/voltage conversion section), and supplies the drive signal to the vibrator via a second signal line, an oscillation detection circuit (oscillation detection section) that detects whether or not the oscillation current has reached a predetermined value after the vibrator has started to oscillate, a startup oscillation circuit (startup oscillation section) that assists an oscillation operation of the vibrator until the oscillation current reaches the predetermined value, and a switch that separates a capacitor from the second signal line until the oscillation current reaches the predetermined value, and connects the capacitor to the second signal line when the oscillation current has reached the predetermined value.

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Nasushiobara, Japan

Toshihiro Nishida