switching power supply

1. Input and output conditions are as follows:
(1) AC input voltage VAc is 170~264V, output current is 2.0A, output voltage is 12V (+1.5%), and output ripple voltage is less than 240mV;
(2) Input and output isolation ;
(3) Within the input voltage range, the power factor PF>0.45;
(4) The efficiency is not less than 89%;
(5) There is no obvious overshoot in the startup output voltage under light load and no-load conditions;
(6) Static power Consumption is less than 200mW.

Please note: Although this project has been verified, some parameters do not meet the standards. This is related to the parameters of the high-frequency transformer and cannot be reflected in the document. The switching power supply is dangerous. Please do not try it casually. The schematic diagram and PCB are for design reference only. Please verify and calculate the specific parameters. We are not responsible for any danger caused by using this open source project.

Some calculation formulas of the design are not reflected, because I used Excel to calculate. Excel involves the copyright issues of the college, so I will not upload it. You can make your own Excel or use other open source ones on the Internet, but if you use open source ones, remember to check and publicize them. Verify, otherwise it will be easy to ascend to heaven hahaha

Reference books:

Pan Yongxiong " Switching Power Supply Technology and Design " ( Second Edition )

Sanjaya Maniktala " Mastering Switching Power Supply Design " ( 2nd Edition )

(The first one written by Teacher Pan is relatively simple, and the second translation is more in-depth and can be read together. I made it by reading the first book)