LED multi-group constant current drive circuit

Abstract

The invention provides an LED (Light Emitting Diode) multi-group constant-current drive circuit, which can be widely applied to the field of LED application. According to the LED multi-group constant-current drive circuit, independent constant-current power supply of multiple groups of LED bead strings can be implemented, the LED bead strings cannot interfere with each other, and LED lamps can be lightened at intervals, so that the junction temperature of the LED bead strings is reduced by more than 20% at work, the light intensity is improved by 1.6 times, the luminous attenuation is reduced, the required radiator area is reduced, and the service life of an LED lamp is prolonged; meanwhile, through changing an input signal of a dimming unit and input data in a data storage unit, the constant current passing through the LED bead strings can be uniformly changed, so that a working mode of the LED bead strings is changed.

Description

technical field [0001] The invention belongs to the technical field of LED constant current drive, and in particular relates to a multi-group LED constant-current drive circuit for realizing independent constant-current power supply for multiple groups of LED lamp bead strings. Background technique [0002] As a new generation of light source, LED light source is developing rapidly. LED is a solid-state semiconductor light-emitting device, which can directly convert electricity into light. It has low energy consumption, strong applicability, high stability, short response time (good switching characteristics), no pollution to the environment, and multi-color light emission. , good color rendering performance and other advantages, it is a new light source worth promoting. [0003] At present, centralized constant current power supply is generally used to drive LED to emit light. According to the size of the LED chip, the power of a single LED is 0.1W, 0.2W, 0.5W, 1W, etc. If...

AI Technical Summary

Problems solved by technology

However, when there is a parallel connection, according to the characteristics of the parallel circuit, the voltage is equal and the current is added, but the total Vf value of each branch LED lamp string is not equal, and the current of the LED lamp string varies. Because the junction temperature is too high for a long time, it will be damaged, and the constant current power supply will add current to other lamp bead strings, forming a vicious circle, which greatly shortens the service life of LED lamps; at the same time, the peripheral required by the existing LED driver chip The circuit is complex and requires more components, resulting in high cost, which greatly hinders the industrialization of LED lighting products.

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