Abstract: A semiconductor integrated circuit device which enables a power-supply voltage terminal and an internal circuit to be isolated from each other in a noncontact operation of a semiconductor integrated circuit device for an IC card, including a first power supply circuit for rectifying and smoothing an AC signal supplied from an antenna, a second power supply circuit which includes a voltage control circuit for controlling a gate terminal voltage of a first MOS transistor, a substrate potential control circuit for forming a source voltage of the first MOS transistor as a substrate voltage, and a second MOS transistor which causes the substrate voltage and the gate voltage of the first MOS transistor to be conductive when using the first power supply circuit, and which causes the substrate voltage and the gate voltage to be nonconductive when using power supplied from an external terminal.

Abstract: A semiconductor intergrated circuit device which enables a power-supply voltage terminal and an internal circuit to be isolated from each other in a noncontact operation of a semiconductor integrated circuit device for an IC card, including a first power supply circuit for rectifying and smoothing an AC signal supplied from an antenna, a second power supply circuit which includes a voltage control circuit for controlling a gate terminal voltage of a first MOS transistor, a substrate potential control circuit for forming a source voltage of the first MOS transistor as a substrate voltage, and a second MOS transistor which causes the substrate voltage and the gate voltage of the first MOS transistor to be conductive when using the first power supply circuit, and which causes the substrate voltage and the gate voltage to be nonconductive when using power supplied from an external terminal.

Abstract: The present invention enables a power-supply voltage terminal and an internal circuit to be isolated from each other in a noncontact operation without largely increasing a chip area in a semiconductor integrated circuit device for an IC card.

Abstract: A monolithic semiconductor integrated circuit device includes a differentially operative circuit section, an amplifying element connected to define a current flowing in the differentially operative circuit section and a circuit for adjusting a current flowing in the amplifying element to thereby compensate for variations of electric characteristics from one semiconductor device to another. The current adjusting circuit includes at least one amplifying element and a load resistance for the amplifying element in the current adjusting circuit. The load resistance has a structure suitable for a trimming operation to adjustably determine the resistance value of the load resistance.