The principle of touching the switch is to pass instructions to the chip through the capacitor or resistance fluctuation generated by the part of the human body close to the switch, and the chip controls the switching circuit to achieve the purpose of opening or closing the electrical appliance. In the process of switching electrical appliances, the human body does not need to contact close contact with high-voltage power sources.
Capacitive induction is more commonly used now, and the general copper foil touch is achieved by using the capacitor to produce a greater change after contact with the human body.