| 摘要 |
PURPOSE:To prevent a malfunction due to noises by connecting a capacitor in parallel between a base and an emitter for an output transistor and charging and discharging the capacitor in response to the ON-OFF operation of a photo- detector. CONSTITUTION:When a phototransistor 102 is turned ON, a transmission signal is output after a fixed delay time from an output transistor 201. When the phototransistor 102 is turned OFF, the transmission signal is output at high speed without the delay time from the output transistor 201. Even when noises are overlapped between a power line and the phototransistor 102 is turned ON instantaneously, the output transistor 201 is left as it is under cut-off because sufficient charges are not stored in a capacitor 202, thus preventing the output of the transmission signal by mistake. |
