| 摘要 |
PROBLEM TO BE SOLVED: To provide a power source control circuit for switching a power source according to current consumption only with hardware elements without inputting any signal from the outside. SOLUTION: A comparator A2 monitors the output currents of an LDO regulator 1, and turns on a DC/DC converter 2 and a switch circuit 5 according as the output currents of the LDO regulator 1 are turned to be a predetermined value or more. Also, a comparator A3 monitors the output level of the DC/DC converter 2, and turns off the switch circuit 5 according as the output level of the DC/DC converter 2 is turned to be the predetermined value or less. Thus, it is possible to switch a power source according to current consumption only by the hardware elements without inputting any control signal from the outside. COPYRIGHT: (C)2004,JPO
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