Protective circuit and radio frequency device using the same

摘要

An RF device has a substrate, a field effect transistor formed on the principal surface of the substrate, a grounded conductor film formed on the back surface of the substrate opposite to the principal surface, and a protective circuit formed between the gate of the field effect transistor and the grounded conductor film. The protective circuit is composed of an inductor or an inductor and a capacitor connected in parallel to each other.