Published:2011/11/13 21:48:00 Author:May | Keyword: High voltage, switching, stabilized voltage supply | From:SeekIC
High voltage switching stabilized voltage supply circuit is shown in the diagram. It is the switching power supply of 80P type color TV. It adopts auto-excitation, PWM circuit. Its output is isolated with power system. This power supply has 110V and 18V DC voltage output. The power supply consists of power frequency rectification filtration circuit, start oscillating circuit, control circuit and DC output circuit.
Input filter composed of capacitors C309, C301 and inductor L301 to weaken the power system interference of power supply. It also can prevent power supply from interfering and polluting. Power frequency rectification filtration circuit composed of VD301~VD304 tochange 220V AC voltage into about 300V DC current. The usage of C304~C307 is to protect the diode form being parallel with them. 300V DC voltage passes starting resistor R302 to reduce voltage, then it will be added to the base of switching compensating pipe VT304, which canmake it to get positive bias and turn on. At the same time, the end of input winding ⑨~② pulse transformer T301 has current. It makes feedback winding 11~⑩ end get positive feedback.
Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/power_supply_circuit/high_voltage_switching_stabilized_voltage_supply_circuit.html
Print this Page | Comments | Reading(3)
Code: