Voice controlled delay light switch circuit (2)

It is a voice- activated delay light switch circuit made by Lizhou SKⅡ type Luzhu integrated circuit . It cleverly uses the first-stage inverting amplifier
between the ⑩ and ⑥ pins inside the integrated block and the frequency selection capacitor between the ④ and ⑤ pins ( 1. Form a delay circuit. The B-foot electret condenser microphone converts the environmental sound wave signal into the corresponding electrical signal , g+ c, which is added to the ① pin of the SK-Ⅱ integrated block and is used by the second-stage inverting amplifier in the integrated block. Amplified, the amplified signal is output from pin 2, coupled through C, sent to pin ③, amplified by the third-stage inverting amplifier and then charged to the frequency selection capacitor C. The input terminal of the first-stage inverting amplifier, pin ⑩, is in the circuit is connected to the ⑤ pin of the frequency selection terminal. Since the voltage at both ends of the capacitor C cannot change suddenly, the output terminal of the first-stage inverse amplifier, that is, the ⑥ pin, is low level, the PNP diode VT is turned on, and the relay K is powered on. The moving contact k] is closed, and the lamp E lights up. After a delay, the output terminal of the first-stage inverting amplifier in the integrated block , that is, pin ⑩, returns to high level, VT is cut off, and the relay K is released, and its moving The closing contact kl jumps open and the light E goes out. This circuit can be controlled by the sound of clapping. Every time you clap your palm, the relay K will act as a suction table. After a delay, the relay K will release itself. The delay time of the circuit is mainly determined by the capacitor [ Determined by the capacity of 3, when G is 1WF', the delay time is about Ss; when G is 47UF, the delay time is about ios; when C. is 100pF, the delay time is about 40s. Readers can adjust it according to their own needs.