US Patent RE49662 Semiconductor integrated circuit and power-supply control method

A semiconductor integrated circuit includes: a first voltage line on which a specific one of a power-supply voltage and a reference voltage appears; a second voltage line; a plurality of circuit cells each receiving power generated as a difference between a voltage appearing on the second voltage line and the other one of the power-supply voltage and the reference voltage; a plurality of switch transistors connected in parallel between the first and second voltage lines to serve as switch transistors including switch transistors each having different conducting-state resistances; and a switch conduction control section for controlling a transition of each of the switch transistors from a non-conducting state to a conducting state by turning on the switch transistors at separate points of time.