| 摘要 |
<p>PURPOSE:To fit an large-capacity external battery on the side of a terminal unit and to lengthen the life of batteries inside a memory card by connecting a protective diode for external connection and a protective resistance for external connection in series to the connector of the memory card. CONSTITUTION:In the internal circuit of the memory card, a protective diode 12 for external connection and a protective resistance 13 for external connection are connected in series to connector of the memory card so that a large-capacity external battery 14 can be connected on the side of the terminal unit in addition to a conventional battery circuit. Generally, the equivalent internal resistance of a battery 5 and the battery 14 is much smaller than a protective resistance 4 and a resistance 13 and therefore, battery capacity can be shown by the sum of the battery 5 and the battery 14. Consequently, when, for example, the battery capacity of the battery 5 is 165mAH and a supply current Isb is 17muA (a ambient temperature is 25 deg.C), when a battery whose capacity is 2,000mAH is mounted as the battery 15, when the ambient temperature is 20 deg.C, the life of the batteries is 14.5 years and is 10 times or above as long as that of only the battery 5. Thus, the life of the batteries inside the memory card can be lengthened.</p> |
