Advantages of self-excited switching power supply
The supplier of the self-excited switching switch is a switching power supply composed of intermittent oscillation circuits, and it is also one of the basic power supplies widely used at present. The switching tube in the self-excited switching power supply plays a dual role of switching and oscillation, and the control circuit is also omitted. In the circuit, since the load is located at the secondary side of the transformer transformer and works in a flyback state, it has the advantage of mutual isolation between input and output. This circuit is not only suitable for high-power power supply, but also for low-power power supply.
Introduction
Self-excited switching power supply is a switching power supply composed of intermittent oscillation circuit, and it is also one of the basic power supplies widely used at present. When the power supply is connected, R1 provides a starting current to the switch tube VT1, so that VT1 starts to conduct, and its collector current Ic increases linearly in L1, and a positive feedback voltage that makes the base of VT1 positive and the emitter negative is induced in L2 , make VT1 saturate very quickly. At the same time, the induced voltage charges C1. As the charging voltage of C1 increases, the base potential of VT1 gradually decreases, causing VT1 to exit the saturation region, and Ic begins to decrease. Induction in L2 makes the base of VT1 negative and the emitter very Positive voltage makes VT1 cut off quickly, at this time diode VD1 is turned on, and the energy stored in the primary winding of high frequency transformer T is released to the load. When VT1 is cut off, there is no induced voltage in L2, and the DC power supply input voltage reversely charges C1 through R1, gradually increasing the base potential of VT1, making it turn on again, turning over again to reach a saturated state, and the circuit continues to oscillate like this . Here, like a single-ended flyback switching power supply, the secondary winding of the transformer T outputs the required voltage to the load.
Advantage
The switching tube in the self-excited switching power supply plays a dual role of switching and oscillation, and the control circuit is also omitted. In the circuit, because the load is located at the secondary side of the transformer and works in a flyback state, it has the advantages of mutual isolation between input and output. This circuit is not only suitable for high-power power supply, but also for low-power power supply.
Self-excited switching power supply is a switching power supply composed of intermittent oscillation circuit, and it is also one of the basic power supplies widely used at present.
