Switching power supply system and self-powered device for switching power supply system

Abstract

The invention relates to a switching power supply system and an auxiliary charging self-power supply device for the switching power supply system. A high-voltage input power supply is connected with a charging capacitor (C1) through an excitation inductor (L1), a power triode (NPN1) and a diode (D1); the charging capacitor (C1) is connected with a power supply end (VCC) of the switching power supply system, a base electrode of the power triode (NPN1) is connected with a control unit. The device comprises a first switch (S1), the on-off of the first switch (S1) is controlled by the control unit, the on-off of the second switch (S2) is controlled by the control unit, the interval time detection module is used for detecting the interval time duration between two excitation stages of the switching power supply system, and the control unit performs the complementary charging of the charging capacitor (C1) by controlling the on-off of the power triode (NPN1), the first switch (S1) and the second switch (S2) according to the interval time duration. According to the invention, the problem of system restart caused by excessive static power consumption of the circuit of the VCC capacitor energy can be effectively solved.

Description

technical field [0001] The invention relates to a switching power supply system and a self-power supply device for the switching power supply system. Background technique [0002] like figure 1 As shown, the existing switching power supply self-power supply device includes a high voltage HV0, an excitation inductor L10, a starting resistor R10, a power transistor Q10, a power NMOS transistor N10, a control chip, a charging diode D10, and a VCC capacitor C10. In the excitation phase of the switching power supply self-power supply device, the control chip drives the power transistor Q10 and the power NMOS transistor N10 for excitation. When the excitation phase is approaching, the control chip stops driving the power transistor Q10 and the power MOS transistor N10. The barrier recovery effect, the current in the excitation inductor L10 can quickly charge the VCC capacitor C10 through the power transistor Q10 and the charging diode D10. When the excitation phase is over, the c...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a switching power supply system and an auxiliary supplementary self-power supply device for the switching power supply system, which can effectively solve the problem of system restart due to excessive consumption of VCC capacitor energy due to excessive static power consumption of the circuit, and optimize the switching power supply The application environment of the circuit realizes the self-power supply of the switching power supply in all states

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