Control chip, primary side control circuit, power converter and control method thereof

Abstract

The invention discloses a control chip, a primary side control circuit, a power supply converter and a control method thereof. The power supply converter comprises the primary side control circuit, the primary side control circuit comprises the control chip, and the control chip comprises a third port. The third port is used for respectively connecting a capacitor and a resistor in parallel with the ground, and the output end of the control chip is connected to a switching tube of a primary side circuit of the power supply converter to control the switching state of the switching tube so as torealize the transmission of electric energy from the primary side circuit to a secondary side circuit. The control chip detects the current signal and the voltage signal of the third port in a time-sharing manner, thereby obtaining a first signal representing the capacitance value of the capacitor and a second signal representing the resistance value of the resistor. According to the control chip, the primary side control circuit, the power supply converter and the control method of the power supply converter, multiplexing of the third port of the control chip is achieved, the number of packaging pins of the control chip is reduced, the packaging cost is reduced, and the implementation cost of the primary side control circuit and the power supply converter is reduced.

Description

technical field [0001] The invention relates to the technical field of electronic circuits, in particular to a control chip, a primary side control circuit, a power converter and a control method thereof. Background technique [0002] The power converter generally includes a primary side circuit and a secondary side circuit connected by a transformer, which transmits electric energy from the primary side to the secondary side circuit, wherein the primary side circuit controls the switching state of the switching tubes connected in series on the primary side circuit through the primary side control circuit Realize the transmission of electric energy. [0003] In the flyback power converter based on secondary side feedback, when the primary side control circuit involves more complex functions, it may need to include power input, grounding, output (output pulse width modulation signal to the control terminal of the switch tube), overload Functions such as protection, sampling ...

AI Technical Summary

Problems solved by technology

[0003] In the flyback power converter based on secondary side feedback, when the primary side control circuit involves more complex functions, it may need to include power input, grounding, output (output pulse width modulation signal to the control terminal of the switch tube), overload Functions such as protection, sampling (adjusting the pulse width modulation signal according to the sampling of the voltage of the primary side circuit), receiving feedback from the secondary side, setting protection parameters, etc. The method of multiplexing or realizing function multiplexing is more complicated, and the packaging cost is higher, which increases the implementation cost of the power converter

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