Inductive automatic switching circuit based on 555 chip

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

One-piece inductor

The inductive automatic switch circuit is as shown in the figure below. When the human body approaches or touches the metal plate, IC1 triggers the flip due to the sensing signal, the 3 pin is at a high level, and the transistor is saturated and turned on; IC2 is triggered by the 2 pin being low. Entering the temporary steady state, the 3 feet are high level, the relay is closed, and the load is connected to the power supply. Conversely, the load is disconnected from the power supply. The timing time is Td=1.1RwC1.