Design And Implementation Of Current-mode Control Principle Of Multi-channel AC-DC Power Supply

In our lives, switching power supply has become an essential part, it is widely used in all aspects of life. Switching power supply can be divided into voltage-control mode and current-control mode, the circuit voltage is sampled only establish feedback is voltage-control mode, and voltage-control mode response is very slow and poor stability, easy to produce shock, so in the voltage-controlled current sampling mode to add a feedback circuit is current-control mode. This topic aims based on a current-mode control theory, design and production of more than one way of AC-DC switching power supplies. The basic requirement is a quad power output(+12V/1A, +5 V/1A), stable work in the city, at different load voltage variation is less than 5%. The main power supply design includes overall design, each part(input and output rectifier filter, PWM control, the main power IC, the output voltage feedback) program selected parts parameter calculation, design and production of high-frequency transformer, circuit welding system and testing. After careful Find information on all aspects of the final selection OB2263 main IC chip, and using flyback topology to design the entire circuit has been tested and meet the requirements of the final circuit output of basic data, and the circuit can be a long and stable working device heating normal.