Switching power adapter base
Sep 07, 2018| What is a switching power supply?
Switching power supply is a kind of power supply that uses modern power electronics technology to control the ratio of time when the switch is turned on and off, and maintains a stable output voltage. The switching power supply is generally composed of a pulse width modulation (PWM) control IC and a MOSFET.
What is the working principle of switching power supply?
Switching power supply is the use of electronic switching devices (such as transistors, FETs, thyristors, etc.), through the control circuit, so that the electronic switching device is constantly "on" and "off", so that the electronic switching device The input voltage is pulse modulated to achieve DC/AC, DC/DC voltage conversion, and adjustable output voltage and auto-regulation.
Switching power supplies generally have three modes of operation: frequency, pulse width fixed mode, fixed frequency, variable pulse width mode, frequency, pulse width variable mode. The former working mode is mostly used for DC/AC inverter power supply or DC/DC voltage conversion; the latter two working modes are mostly used for switching regulated power supply. In addition, the switching power supply output voltage also has three working modes: direct output voltage mode, average output voltage mode, and amplitude output voltage mode. Similarly, the former mode of operation is mostly used for DC/AC inverter power supply, or DC/DC voltage conversion; the latter two modes of operation are mostly used for switching power supply.
Detailed description of switching power supply circuit
The main circuit
The entire process from AC grid input and DC output, including:
1. Input filter: Its function is to filter the clutter existing in the power grid, and also hinder the clutter generated by the machine from being fed back to the public power grid.
2. Rectification and filtering: The AC power supply of the power grid is directly rectified into a smoother DC power for the next level of transformation.
3. Inverter: The rectified DC power is changed into high frequency AC power, which is the core part of the high frequency switching power supply. The higher the frequency, the smaller the ratio of volume, weight and output power.
4. Output rectification and filtering: Provide stable and reliable DC power supply according to load requirements.