555 TV set automatic shutdown controller circuit diagram

Single chip microcomputer STM32L151CCU6

Mobile phone crystal 3.2*2.5mm 3225 26M (26.000MHZ) 7.5PF 10PPM 20PPM 30PPM

Probe domestic switch needle KG300B head diameter 3.0 normally closed switch needle total length is 5

Photocoupler

As shown in the figure, the TV automatic shutdown control circuit. When there is a TV program, the synchronization signal from point A makes BG1 saturated, BG2 and BG3 are turned on, so that 555 is set because the 2 pin is low level, and the high level of the 3 pin output makes JB suck. When the J1 is closed and the TV power supply is turned on; when the TV station finishes the program, the synchronization signal disappears, then BG1 and BG2 are turned off. The C2 that has been charged is discharged through the emission junctions of R5 and BG3, so that BG3 maintains an on-time of about 10 minutes, so as to avoid the undue shutdown caused by intermittent or changing of the program. When C2 is discharged until BG3 is turned off, 555 is reset due to the high level of pin 6. The low level of the output of pin 3 causes relay JB to be released, and J1 is turned off, thereby cutting off the power of the TV.

The controller automatically shuts down after the television program is broadcast according to the synchronization signal of the full television signal as the television program is broadcasted (ie, stops transmitting), detects the presence or absence of it, and controls the power of the television. The power of the TV can save electricity.