LED constant current power source circuit

Abstract

An LED constant current power source circuit comprises an input protection circuit module, an EMI filtering circuit module, a rectification filtering circuit module, a power conversion circuit module, a direct current output circuit, a voltage stabilization constant current circuit module, a feedback circuit module, a PWM control circuit module, a PFC circuit module and a sampling circuit module, wherein the current sampling circuit module, the feedback circuit module and the PWM control circuit module are combined together, and the functions of overvoltage/ overcurrent protection and output short-circuit protection are achieved. When the voltage or the currents of an output end is detected to be abnormal, the signal is fed back to the PWM control circuit module through the feedback circuit module, and an IC in the PWM control circuit module outputs a corresponding signal to enable the power source circuit to stop output work, so that an LED lamp connected with the power source circuit for use is protected. Meanwhile, the LED constant current power source circuit has the advantages of being high in constant current accuracy, high in reliability, simple in circuit structure, low in cost and the like.

Description

technical field [0001] The invention relates to a power supply circuit, in particular to an LED constant current power supply circuit. Background technique [0002] LED (Light Emitting Diode, light-emitting diode) has the advantages of environmental protection, energy saving, long life, high brightness, etc. As a new type of green light source product, LED must be the trend of future development. The era of new lighting sources. At present, LEDs are generally driven by a DC constant current source, but some existing LED constant current power sources have disadvantages such as low constant current accuracy and complicated circuits. Contents of the invention [0003] In order to overcome the deficiencies and existing problems of the prior art, the present invention provides an LED constant current power supply circuit with high constant current precision, simple circuit structure and low cost. [0004] The present invention is achieved through the following technical solu...

AI Technical Summary

Problems solved by technology

At present, LEDs are generally driven by DC constant current sources, but some existing LED constant current power supplies have disadvantages such as low constant current accuracy and complicated circuits.

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