| 摘要 |
PURPOSE: An apparatus is provided to reduce costs and achieve improved stability of circuit, while lengthening the useful life of the lamp and preventing waste of power. CONSTITUTION: An apparatus comprises a battery charge circuit(20) including a comparator amplifier(U1) and transistors(Q1,Q2); a power down detector(60) including a power smoothing section and inverters(U2,U3); a battery low voltage detector(90) including a voltage comparator(U6) for comparing a reference voltage and voltages distributed by distributor resistors(R13,R14) and outputting a low voltage detection; an overcurrent detector(110) including a voltage comparator(U7) for comparing an abnormal voltage and voltages distributed by distributor resistors(R15,R16) and outputting an overcurrent detection signal; a load error detector(120) including a diode(D8) and a condenser(C6), and a voltage comparator(U8) for comparing a reference voltage and the rectified voltage and outputting an abnormal load detection signal; a relay control circuit(70) including a transistor(Q3) and a latch circuit(U4) for receiving signals from the power down detector, battery low voltage detector, overcurrent detector and the load error detector; a relay K1(30) for performing a switching operation for supplying power of a battery(80) by the turn-on operation of the transistor of the relay control circuit; a relay K2 including a D-contact constituted by first and second terminals connected to a fluorescent lamp; and a high voltage generating circuit(40) for receiving power from the battery and generating high voltage current, and which includes an oscillating transformer(T2) having a primary side connected to the overcurrent detector and a secondary side connected to the D-contact of the relay K2 during an emergency turn-on operation.
|
