Patent ID: 7327630

Claim:
A semiconductor device, comprising: a first power switch configured to selectively output a first power supply voltage as a device power voltage in response to a first applied switch control signal; a second power switch configured to selectively output a second power supply voltage as the device power voltage in response to a second applied switch control signal; a third power switch configured to selectively output a third power supply voltage as the device power voltage in response to a third applied switch control signal; and a device power control unit for controlling states of the first, second and third switch control signals so that the device power voltage is supplied as the third power supply voltage when the device is in a standby state and that the device power voltage is supplied as the second power supply voltage during a predefined period of time and next as the first power supply voltage when the device is switched from the standby state to an operating state, wherein the first power supply voltage is lower than the second power supply voltage, and the third power supply voltage is lower than the first power supply voltage.