Charging circuit and charging device used for portable lamps

Abstract

The invention discloses a charging circuit used for portable lamps. The charging circuit for the portable lamps comprises a constant voltage module, a voltage detection module, a voltage comparator and an overcurrent protection diode D2. The constant voltage module is connected between a charging power source and a charging battery. The voltage detection module is connected with the constant voltage module and the charging battery so that voltage output to the charging battery can be detected. When the charging battery is detected to be fully charged, the voltage output of the constant voltage module is closed so that protection of the charging battery is achieved. An output end of the voltage comparator is connected with a voltage feedback sampling end of the constant voltage module through the overcurrent protection diode D2. An inverted input end of the voltage comparator is connected with the same end of the constant voltage module through a first divider resistor R8, and connected to the ground through a second divider resistor R9. A non-inverting input end collects voltages at two ends of a sampling resistor at the position of a negative electrode of the charging battery and closes the constant voltage module when the sampling voltages are larger than voltage of the inverted input end so as to protect the charging circuit. In addition, further disclosed is a charging device.

Description

technical field [0001] The invention relates to the field of lighting appliance charging, in particular to a charging circuit and a charging device for portable lamps. Background technique [0002] With the continuous development of science and technology and the continuous innovation of new materials and technologies, lithium-ion batteries are widely used as a new type of electrical energy storage medium. It has the advantages of high energy density, high output voltage, small self-discharge, no memory effect, long cycle life, etc. The manufacturing process technology has matured and has been widely used in various fields, especially in the field of portable lamps (torches, etc.) power supply. [0003] At present, there are various charging circuits for charging lithium-ion batteries. Among them, the switching power supply as the intelligent control charging circuit is more common. It has the advantages of simple design, convenience and flexibility, and mature technology. ...

AI Technical Summary

Problems solved by technology

[0003] At present, there are various charging circuits for charging lithium-ion batteries. Among them, switching power supply is the most common circuit for intelligent control charging. It has the advantages of simple design, convenience and flexibility, and mature technology, and is widely used by people. However, this circuit The output voltage accuracy is low, and the output power cannot be effectively controlled, which will cause the lithium-ion battery to be undercharged or overcharged, causing damage to the battery, affecting the service life of the battery, and bringing great inconvenience to the user.

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