MEMORY CARD

摘要

PROBLEM TO BE SOLVED: To improve the secrecy of the memory content of a memory card to a third person by detecting the states of a switch group to respective contacts and controlling the supply of back up voltage to a memory element. SOLUTION: A first switching circuit 9 is connected to a second terminal 14 and a detection circuit 8 and it is turned on only when a permission signal is supplied from either a second terminal 14 or the detection circuit 8. Voltage is supplied to an SRAM 6 when the switching circuit 9 is turned on and the memory content of the SRAM 6 can be kept. The detection circuit 8 outputs the permission signal only when the contact points of the respective dip switches in the switch group 7 are in a prescribed state. Thus, the permission signal is not supplied to the switching circuit 9 which the memory card 1 is taken out from an electronic unit and the respective contact points of the switch group 7 are not in the prescribed state. Thus, the switching circuit 9 is turned off and the memory content of the SRAM memory element cannot be kept as a result.