| 摘要 |
PROBLEM TO BE SOLVED: To constitute a first control section and a second control section so that the first control section will start up after the second control section starts up at start-up by placing a switching circuit between the supply voltage input terminals of the first and second control sections which is turned on when the potential of the supply voltage input terminal of the second control section is increased over a given value. SOLUTION: A switching circuit 13, comprising a Zener diode ZD31, resistors R33, R34, a n-p-n transistor TR32 and a p-n-p transistor TR31, is connected between the supply voltage input terminal Vcc1 of a first control section IC1 and the supply voltage input terminal Vcc2 of a second control section IC2. The switching circuit 13 turns on the p-n-p transistor TR31 when the potential of the supply voltage input terminal Vcc2 of the second control section IC2 is increased over a given value. This makes it possible to start up the first control section IC1 after start-up of the second control section IC2 at start-up, and thus to reduce current consumption. |
