LED constant current driving circuit

Abstract

The invention relates to an LED constant current driving circuit which comprises a rectifying circuit (100), a decompression voltage stabilization circuit (200) connecting with a DC output end of the rectifying circuit (100), a constant current circuit (300) including a control module U2, a control circuit (400) using software to change and control the current output by the constant current circuit (300), and an LED load circuit (500); wherein the control circuit (400) comprises a singlechip U1 and a control switch S2; a current detection end of the control module U2 in the constant current circuit (300) is connected with a load, and a regulation end thereof is connected with the control circuit (400), so that constant current control can be provided for an LED. When differential pressure between input and output of the LED constant current driving circuit is high, stable and reliable current still can be output, and the output current can be controlled by the software, so that the LED constant current driving circuit is applicable to multiple application requirements, and has the advantages of simple circuit, higher electrical efficiency, and being beneficial to energy conservation and environmental protection.

Description

technical field [0001] The present invention relates to a power supply drive circuit, more specifically, to an LED constant current drive circuit. Background technique [0002] Today, high energy efficiency, energy saving, and environmental protection have become the general requirements of society for light sources. The traditional incandescent lamp converts a large amount of electrical energy into heat energy, and its energy efficiency is very low. Although the energy efficiency of fluorescent lamps has been improved, they are still relatively low, and their color rendering is relatively poor and they cause great environmental pollution. Light-emitting diode LED lights are widely used in urban greening lighting, mine lights, flashlights, and indoor and outdoor lighting of motor vehicles due to their high energy efficiency, energy saving, environmental protection, uniform spectral distribution, long life, small size, low cost, and low-voltage controllable characteristics. ...

AI Technical Summary

Problems solved by technology

However, the common current limiting method is to connect the LED in series with the current limiting resistor, so the working current of the LED is still not stable enough, and its power consumption is large and the electrical efficiency is low.

For example, the invention patent with the patent application number of 200610026390.5, although its constant current method makes the current stable, but its circuit is complicated, and its constant current is fixed, so the brightness of the light-emitting diode is fixed, which cannot be changed according to people's requirements and has a wide range of applications. Small

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