Field effect transistor logic circuit with reduced power consumption

Abstract

There is disclosed a field effect transistor logic circuit having an output terminal to be connected to a gate of an input field effect transistor in a next stage field effect transistor logic circuit. The field effect transistor logic circuit includes a depletion transistor having a drain connected to a first power supply voltage, an enhancement transistor having a drain connected at a node in common to a gate and a source of the depletion transistor. A gate of the enhancement transistor is connected to an input terminal, and a source of the enhancement transistor is connected to a second power supply voltage which is lower than the first power supply voltage. A high level potential limiting circuit is connected between the node and the output terminal, to lower a potential of the output terminal to a level which turns on a drain-source channel of the input field effect transistor of the next stage field effect transistor logic circuit but which never turns on a gate-source of the input field effect transistor of the next stage field effect transistor logic circuit, when the potential of the node is at a high level. A lower level lowering circuit having an input connected to the input terminal, is also connected between the output terminal and the second power supply voltage, for pulling down the potential of the output terminal to the potential of the second power supply voltage when the potential on the node is at a low level.