| 摘要 |
PURPOSE:To obtain a detection signal which has preferably linearity proportional to the output current with a simple circuit configuration by providing a current detecting resistor between an inverter and a DC power source, and driving a transistor, photocoupler by the voltage difference between both terminals to produce the detection signal. CONSTITUTION:A resistor 19 which is connected to the base B of the first transistor (TR) 5 and the emitter E of the second TR6 are connected to the connecting point of a current detecting resistor 4 and a smoothing condenser 2, and a resistor 20 which is connected to the E pole of the first TR5 and the B pole of the second TR6 is connected to the connecting point of the resistor 4 and the inverter 3. Further, the cathode of LEDs of the first and second photocouplers 7, 8 are connected to the collector of the first and second TR5, 6, and connected at the anode to the condenser 2 through resistors 9, 10. Further, the light receiving sides of the photocouplers 7, 8 are connected to the DC constant voltage source of a control circuit. |
