| 摘要 |
<p>PURPOSE:To reduce the power consumption of a battery, by supplying the voltage of the battery only to a volatile memory such as a dynamic memory, etc. in case the power supply is interrupted. CONSTITUTION:When a switch 1 is applied, the AC power supply 100V is applied to power supply circuits 2 and 3 to produce the DC voltage. Service interruption circuit 5 receives no supply of voltage from a battery 4, and a service interruption circuit 6 receives the supply of voltage from the battery 4 respectively when the power supply is interrupted. For the circuits 5 and 6, contacts 11a-11j of a relay 11 are closed by the relay signal supplied from a CPU8. Thus the circuits 5 and 6 are electrically connected to each other. When the AC power supply is interrupted and the DC voltage of the circuits 2 and 3 lower down to a prescribed level of voltage, a power supply interruption detecting circuit 7 feeds the relay drive signal to the relay 11 to turn off the relay 11 and to separate the circuit 5 from the circuit 6. At the same time, an address switch circuit 17 witches the refresh address signal given from a refresh address counter 21 to a dynamic memory 20.</p> |
