Patent ID: 8365309

Claim:
A memory device comprising: a recording medium including a memory in at least a part thereof; a recording media controller electrically connected to the recording medium and configured to control operations of writing of data to the memory, reading out of data from the memory, and erasing of data of the memory; an accumulator electrically connected to the recording medium and configured to supply a first electric power to the recording medium; a charging circuit electrically connected to the accumulator; a memory unit storing an identification information and data about a length of time during which the charging circuit operates; an authenticator electrically connected to the charging circuit and the memory unit and configured to be input a personal identification information; a first input/output portion electrically connected to the recording media controller and configured to receive data written to the recording medium and to send data stored in the recording medium; and a second input/output portion electrically connected to the charging circuit and configured to receive a second electric power used for charging the accumulator to supply the first electric power, wherein the memory device is configured to perform the operations of writing of data to the memory, reading out of data from the memory, and erasing of data of the memory by using the accumulator as sole source of power, wherein the authenticator is configured to compare the identification information and the personal identification information and to make an authorization to charge the accumulator when the identification information and the personal identification information correspond to each other, and wherein the charging circuit is configured to perform charging of the accumulator during the length of time when the authorization of the authenticator is obtained.