Switching power supply controller, switching power supply system and switching power supply system power supply method

Abstract

The invention provides a switching power supply controller, a switching power supply system and a switching power supply system power supply method. The switching power supply controller comprises a built-in energy storage unit, a power switching tube sampling unit with a power switching tube, a driving unit and a logic control unit which are positioned in the same packaging body, wherein the driving unit is used for driving the power switching tube to be switched on or switched off under the control of the logic control unit so as to adjust the output voltage of the switching power supply system, and the built-in energy storage unit is used for supplying power to the logic control unit. According to the invention, the hardware consumption of the switching power supply system can be saved,the system power consumption is reduced, and the limitation on the size of the built-in energy storage capacitor is avoided.

Description

technical field [0001] The invention relates to the technical field of switching power supplies, in particular to a switching power supply controller, a switching power supply system and a power supply method for the switching power supply system. Background technique [0002] High-side buck (high-side buck) AC-DC switching power supply systems are widely used in household appliances and electric meters. Standby power consumption, better EMI performance, better usage flexibility, and lower cost. [0003] figure 1 It is a commonly used high side buck AC-DC switching power supply system. The voltage on the AC side of the power grid is rectified by a rectifier bridge composed of diodes D1, D2, D3, and D4, and then output as an output voltage DC OUT after being controlled by the control chip U0, and DC OUT is a fixed value. The output voltage DC OUT supplies power to the subsequent load, and in this switching power supply system, when working stably, the operating voltage (th...

AI Technical Summary

Problems solved by technology

The output voltage DC OUT supplies power to the subsequent load, and in this switching power supply system, when working stably, the operating voltage (that is, the supply voltage) VCC of the control chip U0 is realized by the output voltage DC out through the diode D6 and the VCC sampling capacitor C3 , the VCC sampling capacitor C3 completes the sampling of the output voltage DC out and the power supply to the control chip U0, that is to say, the power supply mode of the control chip U0 is the power supply mode of the output voltage. This power supply mode of the control chip has good standby power consumption. However, since the VCC sampling capacitor C3 is required, and the sampling of the output voltage DC out is not direct sampling, the load regulation and dynamic characteristics of the output voltage DC out are poor.

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