What Is A Switching Power Supply

Switching power supply is a power supply that uses modern power electronics technology to control the time ratio of switching on and off to maintain a stable output voltage. Switching power supplies are generally composed of pulse width modulation (PWM) control ICs and MOSFETs. Compared with switching power supply and linear power supply, the cost of both increases with the increase of output power, but the growth rate of both is different. The cost of the linear power supply is higher than that of the switching power supply at a certain output power point, which is called the cost reversal point. With the development and innovation of power electronic technology, switching power supply technology is also constantly innovating, and this cost reversal point is increasingly moving to the low output power end, which provides a broad development space for switching power supply.

The high frequency of the switching power supply is its development direction. The high frequency makes the switching power supply miniaturized and makes the switching power supply enter a wider range of applications, especially in the application of new technologies, which promotes the miniaturization and lightness of new technology products. change. In addition, the development and application of switching power supply are of great significance in saving energy, saving resources and protecting the environment. The power electronic devices used in switching power supplies are mainly diodes, IGBTs and MOSFETs. SCR has a small number of applications in switching power supply input rectifier circuits and soft-start circuits. GTR is difficult to drive and has low switching frequency, and is gradually replaced by IGBT and MOSFET.