Patent ID: 7808334

Claim:
An oscillation driver circuit that is connected to a physical quantity transducer to form an oscillation loop and causes the physical quantity transducer to produce driving vibrations by applying a rectangular-wave drive signal to the physical quantity transducer, the oscillation driver circuit comprising: a drive current/voltage conversion amplifier circuit that converts a current signal from the physical quantity transducer into a voltage signal; and a comparator that receives the voltage signal output from the drive current/voltage conversion amplifier circuit through an input node, outputs a drive signal through a first output node, and outputs a synchronous detection reference signal through a second output node, the comparator including: a differential section that compares the voltage signal input from the 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 the synchronous detection reference signal, a voltage amplitude of the synchronous detection reference signal being fixed.