555 chip is used to form a low power timing switch circuit

Probe domestic switch needle KG-300K needle head diameter is 3.0mm normally open switch needle

Memory chip

The low-power timing switch circuit is shown in the figure below. This circuit reduces the quiescent current of 555 to 1~2μA by adding electronic switches composed of F1, F2 and BG1. After the power is turned on, the C2 voltage cannot jump, F2 outputs a high level, F1 outputs a low level and BG1 is turned off, and the quiescent current of the entire circuit is small. When the button is pressed, F1 outputs a high level, BG1 is turned on, and 555 has a power supply. At the same time, the negative pulse generated by pressing the button is added to pin 2 of 555 to reset it, and the timing of the relay pull-in starts.