Buck circuit

Abstract

The invention discloses an improved buck circuit and relates to the technical field of switching power supplies and controllers. The improved buck circuit comprises a master control circuit, a single-chip microcomputer and an MOS driving module, wherein the master control circuit comprises an inductor L3, a diode D1, an MOS tube Q2, an MOS tube Q3, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C2, a capacitor C3, a capacitor C4, an electrolytic capacitor EC3 and an electrolytic capacitor EC6. The improved buck circuit is simple, reliable and easy to implement. By means of the single-chip microcomputer, two PWM waveforms can be generated, a phase of one PWM waveform is 180 degree larger than that of the other PWM waveform, and the work frequency of a main circuit is increased by one time or more times. When applied to a buck power supply, the improved buck circuit has the advantages of increasing the work frequency of buck by two times, reducing capacity of input capacitors and output capacitors, decreasing inductance values and volumes and reducing volumes and cost of products within a certain range.

Description

technical field [0001] The present invention relates to the technical field of switching power supplies and controllers, and more specifically, to an improved buck (step-down conversion) circuit. Background technique [0002] With the development of society, electronic products are constantly updated, and power supply technology has achieved unprecedented development. The switching speed is getting faster and faster, the power is getting bigger and bigger, and the scope of application is getting wider and wider. For example, our air conditioner controller, washing machine Controllers, refrigerator controllers, solar controllers, led drive circuits, etc. all need power circuits, most of which use buck circuits. In order to achieve intelligence, many of them use single-chip microcomputer control. However, most of the current bucks use traditional single-phase circuits. Due to the influence of components and circuit architecture, traditional buck circuits have the following dis...

AI Technical Summary

Problems solved by technology

[0003] 1. The pwm output frequency of ordinary single-chip microcomputer is low;

[0004] 2. The pre-stage filter capacitor has a large capacity;

[0005] 3. The post-stage filter capacitor has a large capacity;

[0006] 4. The inductance of the energy storage inductor is large and the volume is large;

[0007] 5. It is difficult to select inductive magnetic materials at high power

[0008] Based on the above points, it is difficult to miniaturize the product, which greatly increases the product cost

Images