To provide a power source circuit which is able to supply stably electric power to various kinds of devices and circuits and moreover be reduced in size.
A power source circuit is provided with a main constant-voltage circuit 20, which is connected to a second feeding line +B that receives electric power from a battery BT, only when a relay RLY is conducted and supplies electric power to a third feeding line DL under a fixed main voltage, an auxiliary constant-voltage circuit 30 which is connected to a first feeding line BATT that always receives electric power from the battery BT and supplies electric power to a third feeding line DL under a fixed auxiliary voltage which is lower than the main voltage, and a stop control circuit 40 which permits the operation of the circuit 30, when the second feeding line +B is supplied with an electric power, and when the power supply to the line +B is interrupted longer than by an allowable period of time, inhibits the operation of the circuit 30. Consequently, the power supply to the third line DL is continued from the circuit 30, even when the power supply to the line +B is interrupted if the power supply to the line +B is restored within the allowable period of time.
KANEKO TSUKASA
TANAKA YASUMITSU
| JPH0538065A | 1993-02-12 | |||
| JPS57211946A | 1982-12-25 | |||
| JPH0627369U | 1994-04-12 |
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