With the rapid development of electronic technology and the enhancement of environmental awareness, efficient and energy-saving power supply system has become the mainstream demand in the market. Switching power supply has been widely used in many fields because of its high efficiency and small size. As one of the core components in switching power supply, MOS transistor plays a vital role in power supply conversion, control and protection.

Composition of switching power supply

Switching power supply is a kind of power supply equipment that converts the input AC or DC energy into the required DC voltage by controlling the switching action of power semiconductor devices (such as MOS tubes). Its main components include main power circuit, control circuit and protection circuit. The main power circuit is responsible for the conversion of electric energy, the control circuit is used to adjust and control the output voltage and current, and the protection circuit protects the power supply and load under abnormal conditions.

Selection recommendation of MOS tube

MOS transistor plays the role of "power converter" and "circuit guardian" in switching power supply. In the process of power conversion, MOS tube processes the input electric energy in the form of high-frequency pulses by fast switching action, thus realizing voltage rise and fall and current control. In the control circuit, MOS transistor can accurately adjust the duty ratio according to the feedback signal to ensure the stability of the output voltage. At the same time, MOS tube also has the function of over-current and over-voltage protection. Once an abnormal situation is detected, it can quickly cut off the circuit to prevent damage to the load and the power supply itself.

In switching power supply, MOS transistors are widely used in various topologies, such as Buck, Boost and Buck-Boost. The following is a typical topology diagram of buck converter, which shows the key position and function of MOS tube in the circuit. Through the above introduction, we can see the importance and wide application of MOS tube in switching power supply.