Abstract: A protection circuit includes a control circuit coupled to a first power-supply wire applied with a first power-supply voltage. The control circuit generates a control voltage in accordance with the first power-supply voltage and an input voltage. A voltage limitation circuit is coupled between a first node applied with the input voltage and a second power-supply wire applied with a second power-supply voltage. The voltage limitation circuit includes a variable resistance unit having a resistance value that changes according to the control voltage. When the first power-supply voltage is not supplied to the protection circuit and the input voltage is larger than a first voltage, the control circuit generates the control voltage such that the resistance value of the variable resistance unit is smaller than that in a case where the input voltage is equal to or less than the first voltage.

Abstract: A receiving circuit includes first input transistors of a first conductivity type including control terminals to which differential input signals are applied; load transistors of a second conductivity type connected between a first wiring to which a first voltage is supplied and first terminals of the first input transistors; second input transistors of the second conductivity type including control terminals to which the differential input signals are applied; a latch circuit connected between a second wiring to which a second voltage is supplied and first terminals of the second input transistors; and conversion transistors of the second conductivity type connected in parallel to the second input transistors, the conversion transistors including control terminals that are connected to output nodes to which the first input transistors and the load transistors are connected.

Abstract: A receiving circuit includes first input transistors of a first conductivity type including control terminals to which differential input signals are applied; load transistors of a second conductivity type connected between a first wiring to which a first voltage is supplied and first terminals of the first input transistors; second input transistors of the second conductivity type including control terminals to which the differential input signals are applied; a latch circuit connected between a second wiring to which a second voltage is supplied and first terminals of the second input transistors; and conversion transistors of the second conductivity type connected in parallel to the second input transistors, the conversion transistors including control terminals that are connected to output nodes to which the first input transistors and the load transistors are connected.

Abstract: A protection circuit includes a control circuit coupled to a first power-supply wire applied with a first power-supply voltage. The control circuit generates a control voltage in accordance with the first power-supply voltage and an input voltage. A voltage limitation circuit is coupled between a first node applied with the input voltage and a second power-supply wire applied with a second power-supply voltage. The voltage limitation circuit includes a variable resistance unit having a resistance value that changes according to the control voltage. When the first power-supply voltage is not supplied to the protection circuit and the input voltage is larger than a first voltage, the control circuit generates the control voltage such that the resistance value of the variable resistance unit is smaller than that in a case where the input voltage is equal to or less than the first voltage.