Integrated circuit having spare parts activated by a high-to-low

Abstract

Disclosed is a semiconductor integrated circuit device comprising a semiconductor chip including a plurality of elements constituting multi-functional circuits and a control signal generating circuit incorporated within the semiconductor chip. The control signal generating circuit includes a variable resistance element which irreversibly changes its resistivity when a voltage having a magnitude larger than a specific level, is applied. The variable resistance element is connected in series with a fixed resistor which is further connected in parallel to the output electrodes of a field effect transistor. A control signal is applied to the input terminal of the transistor when the resistance of the variable resistance element is intended to change. An output terminal connected to the connection of the serial connected elements indicates logical '1' or '0' depending on whether the variable resistance element is in the high resistivity state or low resistivity state. In the semiconductor integrated circuit, the output of the control signal generating circuit is transmitted to at least one of the multi-functional circuits, so that it is activated or left deactivated.