| 摘要 |
PROBLEM TO BE SOLVED: To reduce power consumption at backup, in an electronic apparatus which is equipped with a memory to store each kind of setting information inside the apparatus, and is so constituted as to back this up at all times. SOLUTION: For this memory backup circuit, a power switch 2 is on the side of b at off (at backup) of the power of an apparatus, and a weak voltage is generated on the secondary side of a power transformer 1 by applying a current to the power transformer 1 through a small capacity (for example, 0.2 μF-0.5 μF) of a capacitor 8, and sufficient voltage for a microcomputer 7 to stop the normal action and perform only the memory retention, of though it is completely insufficient to operate the apparatus, can be obtained. |
