Reversed polarity protection circuit of power supply

Abstract

The invention discloses a reversed polarity protection circuit of a power supply. The reversed polarity protection circuit comprises an electronic switch, a pump power supply driving circuit and a reversed polarity detection circuit, wherein the electronic switch comprises a first end connected with a power supply input end, a second end connected with a power supply output end, and a control end; the pump power supply driving circuit is connected with the second end of the electronic switch and is used for generating driving voltage higher than power supply input voltage when a power supply is in normal polarity; the reversed polarity detection circuit is connected with the first end and the control end of the electronic switch; when the power supply is in normal polarity, the reversed polarity detection circuit is driven by the driving voltage generated by the pump power supply driving circuit and outputs control signals for conducting the first end and the second end of the electronic switch, to the control end of the electronic switch; and when the power supply is in reverse polarity, the reversed polarity detection circuit is used for outputting control signals for disconnecting the first end and the second end of the electronic switch, to the control end of the electronic switch. The reversed polarity protection circuit disclosed by the invention can be used for controlling the conduction and the disconnection of the input end and the output end of the power supply conveniently, rapidly and effectively so as to protect terminal equipment at the output end of the power supply.

Description

technical field [0001] The invention relates to the field of power supplies, in particular to a power supply reverse polarity protection circuit. Background technique [0002] Nowadays, the automobile industry is developing rapidly, and the number of automobiles is increasing. While owning a car, people will also pay more and more attention to the experience of using the car. The vehicle-mounted terminal on the car can realize services including music, video, pictures and other multimedia needs, as well as real-time traffic signals, destination maps and other driving signals. demanded services, etc. These many services of the vehicle terminal must provide the power required for operation through the vehicle power supply on the car, but when the polarity of the power supply is reversed, it will cause damage to the functional modules of the vehicle terminal. [0003] There is a fuse between the power supply and the functional modules of the existing vehicle-mounted terminal,...

AI Technical Summary

Problems solved by technology

Although this method can protect the vehicle terminal, it is troublesome to replace the fuse F0

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