Abstract: In a USB device comprising a plurality of functional modules that includes a control circuit for switching a functional module to be activated from among the functional modules included in the USB device according to a potential level of a power applied from a host connected to the USB device. The control circuit includes: a voltage detector for discriminating a voltage value of power; a switch for controlling powers to be applied to the respective functional modules; and memories for storing descriptors relating to the USB device. The control circuit makes power applied to a functional module to be activated by the switch into ON state according to a discrimination result of the voltage value of the power by the voltage detector, thereby transferring the descriptors stored in the memories to a host.

Abstract: In a SIM card having a flash memory chip, a memory controller chip, and contact/contactless card interfaces, the memory controller chip has a function of executing user authentication of a host equipment, executes processing of data transmitted through the contactless IC card interface (executing reading or writing of data to the flash memory chip) using power supplied from the host equipment to the contact IC card interface, and executes initialization of the flash memory chip between activation of the host equipment and completion of user authentication instructed by the host equipment.

Abstract: A memory card, which is a storage device connectable to a terminal, includes a buffer memory in which externally-provided data is stored, a flash memory, and a controller which controls reading and writing of data from and to these memories. The controller saves a divided input data in the non-volatile memory in accordance with a result of determination regarding data size information contained in a first divided input data of data externally inputted for a security process and a data management size of the storage device, and the controller reads the saved data to the memory for performing the security process when it receives an n-th divided input data.

Abstract: In order to protect the user security data, provided is a memory card capable of preventing the data leakage to a third party not having the access authority by imposing the limitation on the number of password authentications and automatically erasing the data. In a system comprised of a multimedia card and a host machine electrically connected to the multimedia card and controlling the operations of the multimedia card, a retry counter for storing the number of password authentication failures is provided and the upper limit of the number of failures is registered in a register. When passwords are repeatedly entered once, twice, . . . and n times and the retry counter which counts the entries reaches the upper limit of the number of failures, the data is automatically erased so as not to leave the data in the flash memory.

Abstract: The memory device of the present invention comprises an interface for receiving time information from a host device; an EEPROM for storing pass-information which is related to the pass-information of a server device and which is defined for each user for the memory device; and a random number generator for generating a passcode ion the basis of the pass-information in the EEPROM and the time information from the host device in response to a request from the host device and sending the passcode to the host device without sending the pass-information to the host device.

Abstract: A storage device allows expanding user utilizable applications by storing information permitted to be read according to a certificate and information permitted to be read according to information determined by a user. An information distributor receives a certificate from the storage device and after verifying the certificate, transmits data of a license and access control conditions to the storage device. After receiving data of a certificate from an information browser, verifying the certificate and imposing a limit on access based upon one of access control conditions, the storage device transmits data of the license and the other to the information browser. The information browser permits utilization of the license under the limitation defined by the access control condition. The certificate includes either or both of a certificate approved by a certificate authority and a PIN (personal identifying number) determined by the user.