CF8865 module using dedicated switching power supply circuit diagram
Posted on Dec 11, 2010 4606
Described here is a specific module using CF8865 switching power supply circuit, because this circuit is the use of integrated control module CF8865 specific modules. In the fi
gure, VT4, VTs is controlled by the excitation transformer Tz job switch, its output down by a pulse transformer T3, followed by stage output voltage bridge rectifier and regulator, the filtered output of plus or minus two symmetrical DC power supply, which is a group of 18V, another group of 50V. CF8865 can produce oscillation pulse 120kHz from 3,4 pin output module through the excitation transformer T and push the switch VT4, VTs work. CF8865 9-pin output voltage adjustment ends, RPi to adjust potentiometer, adjust Wei, you can change the output voltage value of 08 feet for the output voltage error sample input voltage. l, 2 feet for the mains input voltage fluctuation sampling control input, since CF8865 3.4 foot addition to the excitation pulse to promote the output transformer Tz VT4, VTs turned off, but also to promote the vrl turned off by another winding. When the mains voltage fluctuations, 300V DC voltage rectifier output will fluctuate, so that by the VTi is turned off amplitude pulses across the primary winding Ti formed will fluctuate after it is coupled to the secondary station via VD4 rectifying generated negative voltage amplitude will be crossing the move, and the potential difference between the change in 2,1 feet, after an internal NIE circuit detection to control the output of 3,4 feet pushing pulse width, and ultimately mains fluctuations caused by fluctuations in the output voltage will be regulated to control.