| 摘要 |
PURPOSE:To prevent an electronic equipment with adding a simple circuit from being misinterrupted by a noise by interrupting a main power supply to the equipment when the interrupted state is again detected in a lapse of a predetermined time after the interrupted state of the equipment was detected in a main control section. CONSTITUTION:When a battery 6 is connected and a power switch 5 is turned ON, pulses on a level L is generated to the collector of a transistor Tr 11, which is inputted into a clock terminal of a D-type flip flop DFF 12, so that the DFF 12 steps and an inverse output outputs a level H to turn ON a Tr 15 and to supply power to a power line 16. If a switch 5 is pushed and the Tr 11 supplies a clock to the DFF 13, the output of DFF 12 remains ON and it interrupts an unillustrated CPU through a signal line 17. The state of the switch 5 is read through a signal line 18 with the CPU after a predetermined time. If the switch 5 is found OFF, the Tr 15 is turned OFF via DFF 13 and 12 through a signal line 10 from the CPU. Misinterruption of power by the noise and by the chattering at a power source can thereby be prevented. |
