| 摘要 |
PROBLEM TO BE SOLVED: To extend the life of a bias protection circuit for protecting a bias circuit for supplying a bias voltage to an amplification device from a supply voltage from a power supply of the amplification device.SOLUTION: A bias protection circuit 4 includes: a first transistor 43 that has a source terminal connected to a bias circuit connection terminal 42 and a drain terminal connected to an amplification circuit connection terminal 41, and controls on/off of a continuity between both terminals 41, 42 on the basis of a voltage applied to a gate terminal; and a second transistor 44 that has a gate terminal fed with a voltage divided from a voltage applied to the amplification circuit connection terminal 41, and if the voltage applied to the amplification circuit connection terminal 41 is a voltage resulting from a short circuit between a power supply and a gate terminal of an amplification circuit, turns on a continuity between a source terminal and a drain terminal to regulate the voltage applied to the gate terminal of the first transistor 43 such that the continuity between both terminals 41, 42 is turned off. |
