| 摘要 |
<p>PURPOSE:To heighten reliability for an IC memory card more than ever by loading a function to send out the residual quantity of the backup battery of the memory card to a system side at the IC memory card. CONSTITUTION:A battery voltage monitoring circuit 204 is provided in addition to semiconductor memory 201, a control circuit 202 which controls read/write on the memory, and a connector 203 for connection to the system side. The information of the residual quantity of the backup battery is sent out to the system side via a battery voltage monitoring signal 214 by the monitoring circuit 204. Therefore, the user of the IC memory card can confirm the state of the residual quantity of the backup battery of the memory card. Thereby, it is possible to eliminate danger to uses erroneous information and to lose significant information, which enables the IC memory card to be used without anxiety.</p> |
