Switch power supply circuit and control method thereof

Abstract

The application discloses a switch power supply circuit and a control method thereof. The switch power supply circuit includes an input port which receives the input signal; an energy storage port which provides the energy storage voltage; an inductor which is provided with a first terminal and a second terminal, wherein the first terminal is coupled to the input port; a power level circuit which is coupled between the second terminal of the inductor and the energy storage port; an energy storage capacitor which is coupled between the energy storage port and the reference ground; a boost controller which receives the feedforward signal which represents the input signal, and outputs the boost control signal to maintain the boost working mode of the power level circuit when the input signal is bigger than a boost threshold; and a buck controller receives the feedforward signal which represents the input signal, and outputs the buck control signal to maintain the buck working mode of the power level circuit when the input signal is smaller than a buck threshold, and the energy storage voltage is bigger than the input signal. The switch power supply circuit and the control method thereof reduce the circuit consumption and improve the system efficiency.

Description

technical field [0001] The present invention relates to an electronic circuit, more specifically, the present invention relates to a switching power supply circuit and a control method thereof. Background technique [0002] In typical digital subscriber line applications, asymmetric digital subscriber loop, and solid-state hard drive applications. In order to supply power to the system when the system is powered off, multiple energy storage capacitors are often coupled together in parallel. But this will increase the system cost. [0003] Storing energy at high voltage and releasing it when power is lost reduces the number of storage capacitors. The existing technology uses a combination of charge pump and LDO (low dropout) circuit to manage energy. The charge pump converts the input signal of the system into a high-voltage signal, and the LDO is responsible for releasing the high-voltage signal when the system is powered off to maintain the system. Work. However, the ch...

AI Technical Summary

Problems solved by technology

At the same time, when the high-voltage signal is released, the power consumption of the LDO circuit is relatively large, which increases the burden on the system and seriously affects the efficiency of the system.

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