| 摘要 |
A double-current detector for generating a rectangular waveform signal substantially in phase with a received double-current signal has a full-wave rectifying bridge circuit having a pair of AC terminals for receiving the double-current signal therebetween, a pair of DC terminals, a first photocoupler including a light-emitting element connected between the DC terminals, and a second photocoupler including a light-emitting element connected in one arm of the bridge circuit. An increase in the double-current signal is detected by using an output signal from the first photocoupler, and the polarity of the double-current signal is detected by using an output signal from the second photocoupler. In response to signals indicative of the increase and polarity of the double-current signal, a logic circuit controls a flip-flop to produce an output signal as the rectangular waveform signal. |
