Patent ID: 8024589

Claim:
An information storage device in an information recording/reproducing device that has a host computer and an information storage device connected to each other via an interface, the interface being provided with a power management mechanism having a first power consumption mode and a second power consumption mode to keep power consumption lower than the first power consumption mode, and the information storage device being provided with an internal power management mechanism having a third power consumption mode and a fourth power consumption mode to keep power consumption lower than the third power consumption mode, the device information storage comprising: power management control means for controlling transition of the power consumption mode of the power management mechanism of the interface based on the current power consumption mode of the internal power management mechanism, wherein, when the power consumption mode of the internal power management mechanism is the third power consumption mode, the power management control means shifts the power consumption mode of the power management mechanism of the interface from the first power consumption mode to the second power consumption mode after the lapse of a first time period from the termination of communication with the host computer, and when the power consumption mode of the internal power management mechanism is the fourth power consumption mode, the power management control means shifts the power consumption mode of the power management mechanism of the interface from the first power consumption mode to the second power consumption mode after the lapse of a second time period shorter than the first time period from the termination of communication with the host computer.