Patent ID: 9276400
Filing Date: 2016-03-01
CPC Classification: H01L,H02H

Claim Text:
1. A protection circuit comprising: a transformer which includes, between a terminal part of an electronic circuit and an input or output of the electronic circuit, a plurality of inductors magnetically coupled therebetween, wherein one end and the other end of a terminal-side inductor of the transformer are connected to the terminal part and a ground, respectively, the electronic circuit is a circuit of a differential configuration, and a circuit-side inductor of the transformer has a midpoint terminal, one end of the circuit -side inductor is connected to an input or output of one electronic circuit of the differential configuration, the other end of the circuit-side inductor is connected to an input or output of the other electronic circuit of the differential configuration, and the midpoint terminal is connected to a bias power supply circuit of the electronic circuit, wherein the bias power supply circuit generates a desired DC voltage at a bias power supply terminal, and the bias power supply circuit has a transistor having a gate, a source, and a drain, and each of the gate and the drain of the transistor is connected to the bias power supply terminal and the source thereof is grounded.