Field effect transistor gate bias voltage application circuit and

Abstract

FET gate bias voltage application circuits and semiconductor apparatuses in which such a FET gate bias voltage application circuit is installed compensate for adverse effects caused by changes in the surrounding temperature. A temperature compensation FET is installed in a FET gate bias voltage application circuit in which a divided voltage is applied to the gate of a controlled FET from a first intermediate point of a resistance type potential dividing circuit to which a direct current voltage is applied. This temperature compensation FET becomes conductive at a gate voltage higher than the gate voltage of the controlled FET. A voltage divided at the first intermediate point is applied to the gate of this temperature compensation FET. The drain of this temperature compensation FET is connected to a second intermediate point at which the electric potential is higher than the electric potential at the first intermediate point. The source of this temperature compensation FET is grounded. This temperature compensation FET remains non-conductive when the gate-drain current of the controlled FET is at a low level. This temperature compensation FET becomes conductive when the gate-drain current of the controlled FET increases to a high level to cause a drain-source current to flow through this temperature compensation FET. As a result, the amount of voltage drop increases at a region in which the electric potential is higher than the electric potential at the second intermediate point of the resistance type potential dividing circuit. This causes the electric potentials at the first and second intermediate points, respectively, to be shifted in the negative direction.