Switching mode power supply input voltage range expansion circuit and design method thereof

Abstract

The invention discloses a switching mode power supply input voltage range expansion circuit and a design method of the expansion circuit. The expansion circuit comprises a first voltage expansion circuit connected between a direct current voltage input circuit and a switching mode power supply chip. The direct current voltage input circuit is an alternating current and direct current converting circuit or a direct current voltage source. The switching mode power supply chip is provided with the overvoltage and undervoltage protection end. The positive pole voltage output end of the first voltage expansion circuit is connected with the overvoltage and undervoltage protection end of the switching mode power supply chip. The negative pole voltage output end of the first voltage expansion circuit is connected with the grounded end of the switching mode power supply chip. The invention further discloses the design method of the switching mode power supply input voltage range expansion circuit. According to the expansion circuit and the design method, implementation is convenient, cost is low, the adaptability of a switching mode power supply to a power grid can be improved, the application range of the switching mode power supply is widened, the work reliability of the switching mode power supply can be effectively improved, practicality is high, and application and popularization are convenient.

Description

technical field [0001] The invention belongs to the technical field of switching power supplies, and in particular relates to a switching power supply input voltage range expansion circuit and a design method thereof. Background technique [0002] With the rapid development of science and technology, the relationship between switching power supply and people is getting closer and closer, and it is playing an increasingly important role in people's daily life. In the prior art, the overvoltage and undervoltage protection range of the switching power supply chip in the switching power supply is generally relatively narrow, for example, the common range is about 1V to 4V, and the overvoltage and undervoltage protection range of the switching power supply chip limits the input of the switching power supply. Voltage range, and, in the prior art, a simple resistor series voltage divider circuit is generally connected between the DC voltage input circuit and the switching power sup...

AI Technical Summary

Problems solved by technology

In the prior art, the overvoltage and undervoltage protection range of the switching power supply chip in the switching power supply is generally relatively narrow, for example, the common range is about 1V to 4V, and the overvoltage and undervoltage protection range of the switching power supply chip limits the input of the switching power supply. Voltage range, and, in the prior art, a simple resistor series voltage divider circuit is generally connected between the DC voltage input circuit and the switching power supply chip, so that the input voltage range of the switching power supply can only be 165VAC ~ 265VAC, and the adaptability to the grid Weaker, and the application of switching power supply is limited, therefore, it is of great significance to design a switching power supply input voltage range expansion circuit

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