Waterproof protection method for low-cost battery charging interface

Abstract

The invention discloses a waterproof protection method for a low-cost battery charging interface. A battery, a direct current charging input interface and a one-way control circuit connected with the battery and the direct current charging input interface are included, and the one-way control circuit is composed of a P-channel field effect transistor D1, a diode D2, a triode Q1, resistors R1, R2, R3, R4 and R5 and a battery circuit. According to the method, on and off of a field-effect transistor are controlled by automatically detecting whether a charging input interface has input voltage by utilizing the advantages of switching characteristic, low on-resistance and low dropout of the field-effect transistor device, so one-way conduction of a circuit is controlled, and the battery is prevented from supplying power to the charging port when no voltage is input to the charging port; when the charging port has no voltage, the field effect transistor is cut off, and the circuit between the battery and the charging port is cut off, thereby effectively preventing the battery from flowing out of the charging port to damage equipment.

Description

technical field [0001] The invention relates to the technical field of waterproofing of a battery charging interface, in particular to a waterproof protection method for a low-cost battery charging interface. Background technique [0002] Many electronic products use a built-in battery for easy portability. In this way, a built-in battery charging interface is often reserved on the device casing to facilitate charging the device when the device is out of power. However, in application scenarios such as rain or underwater, there will be a voltage difference between the two electrodes of the reserved interface. After the circuit at the interface contacts electrolyte such as water, it will electrolytically corrode the reed of the interface electrode and even directly cause a short circuit of the equipment circuit, resulting in equipment damage. . Therefore, such electronic devices usually have a built-in battery charging management circuit or physically seal the charging inter...

AI Technical Summary

Problems solved by technology

[0003] When using physical sealing to protect the equipment from water, it will increase the cost of shell abrasives, affect the appearance of the shell, increase the difficulty of shell design and low reliability, and it is easy to cause damage to the equipment due to vibration and other reasons

When using the charging management circuit, the commonly used methods are the charging and discharging management chip and ordinary diodes to construct the anti-reverse circuit. The charging and discharging management chip solution has high security and stability, but the cost will be relatively high

The cost of building an anti-backflow circuit with ordinary diodes is low, but ordinary diodes have a large leakage current. After the charging interface contacts water and other electrolytes, the metal reed will be slowly decomposed and corroded, which will affect the service life of the device.

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