Patent ID: 7940138

Claim:
An oscillation circuit comprising: an amplifier for feedback-controlling a solid-state oscillator; and ESD protecting circuits respectively connected to input and output sides of the amplifier, wherein the ESD protecting circuit on the input side of the amplifier comprises an ESD protecting element whose constituent is a diode having a P-type diffusion layer and an N-type diffusion layer, the ESD protecting circuit on the output side of the amplifier comprises an ESD protecting element whose constituent is a MOS transistor, and the ESD protecting circuit on the input side of the amplifier comprises: a power-supply-side ESD protecting element; and a ground-side ESD protecting element, wherein a diode in which an N-type diffusion layer is connected to a power-supply wire and a P-type diffusion layer is connected to the input side of the amplifier constitutes the power-supply-side ESD protecting element, and a diode in which a P-type diffusion layer is connected to a ground wire and an N-type diffusion layer is connected to the input side of the amplifier constitutes the ground-side ESD protecting element.