A LED backlight two-in-one power supply and an LED backlight display

Abstract

The invention belongs to the technical field of LED backlight display, and provides a two-in-one power source for LED backlight and a LED backlight display. The two-in-one power source for LED backlight is characterized in that LED load is equivalent to stable voltage and is subjected to current sampling by a sampling circuit; a sampling circuit of the sampling circuit is amplified by virtue of a constant current control circuit; corresponding duty cycles of an excitation control circuit are regulated according to the output of the constant current control circuit; meanwhile, the voltage is subjected to buck conversion by utilizing direct current-direct current conversion circuit and the electricity is supplied to a main board. The circuit can normally work in a relatively-wide input voltage range; compared with the prior art, the two-in-one power source has the advantages that a BOOST circuit is eliminated, the structure is simple, the cost is low, and the conversion rate can reach 82 percent; meanwhile, boost inductance is not needed, and the problem of poor circuit reliability and the like possibly caused by the boost inductance can be solved.

Description

technical field [0001] The invention belongs to the technical field of LED backlight display, and in particular relates to an LED backlight two-in-one power supply and an LED backlight display. Background technique [0002] At present, in the field of liquid crystal display technology, light-emitting diode (Light-Emitting Diode, LED) backlights are widely used to replace traditional cold-cathode fluorescent lamps (Cold Cathode Fluorescent Lamp, CCFL) backlights to improve display effects. [0003] In order to meet the low-cost requirements of the display industry, LED backlight two-in-one power supplies are usually used in current LED backlight displays. This type of power supply can simultaneously realize the light-emitting drive of the LED backlight module and the power supply of each circuit on the main board of the LED backlight display. [0004] In the prior art, the LED backlight two-in-one power supply generally adopts an integrated architecture of a stable and relia...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the embodiments of the present invention is to provide a LED backlight two-in-one power supply, aiming at solving the problem that the existing LED backlight two-in-one power supply uses an integrated architecture of a flyback power supply and a BOOST booster circuit, which makes the circuit structure complex and the product Problems of high cost, low conversion efficiency and poor reliability

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