How does a switch work?

A switch is an electrical component used to control the on and off of a circuit. Its working principle is mainly to control the conduction and disconnection of the conductive material in the circuit to achieve the on and off of the circuit. The working principle of the switch can be divided into two types: mechanical switch and electronic switch.

Mechanical switches are the earliest type of switches. Their working principle is to achieve the on-off of the circuit through a mechanical structure. Mechanical switches are usually composed of conductive materials and insulating materials. When the switch is in the closed state, a path is formed between the conductive materials, and the current can flow; when the switch is in the open state, the conductive materials are disconnected and the current cannot flow. The operating principle of the mechanical switch is to make the conductive materials contact or separate by manual or external force, thereby achieving the on-off of the circuit.

An electronic switch is a switch that uses semiconductor devices to turn a circuit on and off. Its working principle is to turn the circuit on and off by controlling the on and off state of semiconductor devices. Electronic switches are usually composed of semiconductor devices such as transistors and field effect transistors. When the electronic switch is in the on state, the current can flow; when the electronic switch is in the off state, the current cannot flow. The operating principle of an electronic switch is to turn the circuit on and off by controlling the working state of semiconductor devices.

Switches play a very important role in circuits. They can realize circuit switch control, circuit branch selection, circuit protection and other functions. In practical applications, there are many types of switches, including push button switches, knife switches, touch switches, sensor switches, etc. Different types of switches have different working principles and applicable scenarios.

In general, the working principle of a switch is to control the conduction and disconnection of conductive materials to achieve the on and off of the circuit. Mechanical switches and electronic switches are two common types of switches. Switches play an important role in circuits, and their stability, reliability and flexibility are crucial to the normal operation of circuits.