Patent ID: 8716918
Filing Date: 2014-05-06
Classification: B06B,G01C,G01D,H01L,H02P

Abstract:
1. A drive circuit adapted to output a drive signal for exciting a vibrator, comprising: a current-voltage conversion circuit adapted to convert an excitation current input into a voltage; a rectifying circuit adapted to perform rectification on an output voltage from the current-voltage conversion circuit; a drive signal generation circuit adapted to generate the drive signal based on the output voltage from the current-voltage conversion circuit; and a comparison control circuit adapted to compare an output voltage from the rectifying circuit with a comparative voltage to thereby control an amplitude of the drive signal, wherein the comparison control circuit includes a comparative voltage supply circuit adapted to supply the comparative voltage, and the comparative voltage supply circuit generates the comparative voltage with a constant current source and a second resistor made of material having a temperature characteristic the same as a temperature characteristic of a first resistor included in the current-voltage conversion circuit.