| 摘要 |
PURPOSE:To prevent malfunction due to noise by providing a pulse train signal detecting section to an infrared ray remote control reception section and inhibiting the operation of a decode circuit within a fixed period after the end of a pulse train signal is detected. CONSTITUTION:A remote control signal of an infrared ray is detected 1, converted it into an electric signal, AM detection is applied so as to convert the signal into a pulse train signal (a), which is inputted to a gate circuit 3. On the other hand, the pulse train signal (a) is inputted to a pulse train signal presence or absence detecting circuit 4, and when the pulse train is detected, a discrimination signal (b) is inputted to a gate control circuit 5. An FF circuit built in the gate control circuit 5 is inverted so as to input a gate control signal to the gate circuit 3. The signal (c) closes the gate circuit 3 for a certain time T after the end of the pulse train signal so as to inhibit the operation of a decode circuit 2. Thus, the malfunction of a decode circuit due to noise after the end of the pulse train in prevented. Moreover, the noise before the start of pulse train is discriminated by the decode circuit 2. |
