CN203376958U

CN203376958U - Large-lower LED lamp bead array for display screen

Info

Publication number: CN203376958U
Application number: CN201320338310.5U
Authority: CN
Inventors: 程圣威; 邓金胜
Original assignee: Shenzhen Dawei Light Source Co ltd
Current assignee: Shenzhen Dawei Light Source Co ltd
Priority date: 2013-06-13
Filing date: 2013-06-13
Publication date: 2014-01-01
Anticipated expiration: 2023-06-13

Abstract

The utility model discloses a large-lower LED lamp bead array for a display screen, and the lamp bead array comprises six LED lamp beads which are in an array with two rows and three columns. Each lamp bead comprises an LED illuminant, an LED drive circuit, a base, and a fixed support, wherein the LED illuminant is located on the LED drive circuit, the LED drive circuit is fixed on the base, the base is fixed on the fixed support, and the fixed support is fixed on a lamp bead panel. Each LED drive circuit comprises a boundary-type boost power factor correction circuit, an active clamping forward converter, and a high-low limit constant-current pulse-width modulation drive dimming circuit, wherein the boundary-type boost power factor correction circuit, the active clamping forward converter and the high-low limit constant-current pulse-width modulation drive dimming circuit are sequentially connected together. A liquid crystal display backlight module serves as an application background, and the luminescence characteristic of a light-emitting diode is analyzed. That the current control is the best mode of LED brightness adjustment is pointed out. In order to obtain higher luminous efficiency and a better dimming effect, the LED drive dimming circuit is designed to be in a three-level structure. Experiments show that the designed LED drive circuit can be used for not only improving the power factor of a system, but also reducing a dominant wavelength of an LED and the drifting of a color coordinate, thereby effectively controlling the brightness of the LED.

Description

Display screen large-power LED light bead array

Technical field

The utility model relates to display technique field, LED-backlit source, more specifically, relates to a kind of display screen large-power LED light bead array apparatus.

Background technology

At present traditional along with social progress and the development of technology, the display device that the characteristics such as the display device of LED (light-emittingdiode Light Emitting Diode) backlight is high with its reliability, long service life, adaptive capacity to environment is strong, cost performance is reasonable, use cost is low substitute traditional C CFL (cathode fluorescent tube Cold CathodeFluorescent Lamp) backlight gradually becomes rapidly the main product that large flat shows, in field of information display, is widely used.The huge market demand impels liquid crystal panel manufacturer and national governments' activity investment to set up LED product line of new generation, in this case, meets 55 inches and following liquid crystal panel 8.5 generation production line and builds like the mushrooms after rain.When various countries actively build 8.5 generation lines, with leading panel vendors such as Korea S's Samsung and Japanese Sharps, especially actively to higher line generation---can meet the 10 generations line investment of 65 inches and above application such as HDTV, exhibition room display and billboard.

The backing structure of 55 inches of traditional LED-backlit source and following display device generally has following two kinds:

1, downward back photo structure

Although on principle, LED array can be made infinity, but the existence due to air layer d, increased undoubtedly the thickness of whole display, because needing a large number of LED, this class display does support simultaneously, also increased from another point of view the energy consumption of display, be unfavorable for the reduction of display use cost, therefore this backing structure can't be made superhuge display device.

2, side entrance back structure

But because current LED brightness range is limit, the light guide plate width also must be restricted, and because this type of design LED luminescence unit is positioned at the periphery of display, so be difficult to fundamentally improve the dynamic contrast of whole display, thereby this backing structure can't be made equally

Superhuge display device.

Thus, need a kind of LED of design can accomplish 65 inches even larger display devices as backlight, size, and if this display device meet the performance requirement of low cost, low energy consumption, high brightness and contrast.

The utility model content

For the problems referred to above, the utility model provides display screen large-power LED light bead array, it is characterized in that: described LED lamp pearl array comprises 2 row 3 row totally six LED lamp pearls, and each lamp pearl comprises: LED luminophor 3, LED drive circuit 2, pedestal 1, fixed support 4, described LED luminophor 3 is positioned on LED drive circuit 2, and driving circuit 2 is fixed on pedestal 1, pedestal 1 is fixed on fixed support 4, and fixed support 4 is fixed on lamp pearl panel 5.Described LED drive circuit comprises connection in turn: Boundary-Type step-up type power factor correction circuit, active clamping forward converter, the spacing constant current width modulation of height drive light adjusting circuit.

The technique scheme of utilizing the utility model to provide, display device can be accomplished to infinity, ultra-thin in theory, and the LED-backlit source display device brightness of manufacturing according to the utility model is high, cost is low, dynamic contrast to, energy-conservation, the utility model adopts LED as backlight, go for 65 inches and above liquid crystal display, can be widely used in the display device that HDTV, showroom display and billboard etc. need high definition, giant-screen.

The accompanying drawing explanation

Describe in more detail exemplary embodiment of the present utility model by the reference accompanying drawing, above and other aspect of the present utility model and advantage will become and more be readily clear of, in the accompanying drawings:

Fig. 1 is large-power LED light bead array cross-sectional view for display screen of the present utility model.

Fig. 2 is large-power LED light bead array drive circuit functional-block diagram for display screen of the present utility model;

Fig. 3 is the circuit theory diagrams of display screen of the present utility model with Boundary-Type step-up type power factor correction circuit in the large-power LED light bead array drive circuit;

Fig. 4 is the circuit theory diagrams of display screen of the present utility model with active clamping forward converter in the large-power LED light bead array drive circuit;

Fig. 5 is that display screen of the present utility model drives the circuit theory diagrams of light adjusting circuit with the spacing constant current width modulation of height in the large-power LED light bead array drive circuit.

Embodiment

Hereinafter, now with reference to accompanying drawing, the utility model is described more fully, various embodiment shown in the drawings.Yet the utility model can be implemented in many different forms, and should not be interpreted as being confined to embodiment set forth herein.On the contrary, it will be thorough with completely providing these embodiment to make the disclosure, and scope of the present utility model is conveyed to those skilled in the art fully.

Hereinafter, exemplary embodiment of the present utility model is described with reference to the accompanying drawings in more detail.

With reference to accompanying drawing 1, Fig. 1 is large-power LED light bead array cross-sectional view for display screen of the present utility model, described LED lamp pearl array comprises 2 row 3 row totally six LED lamp pearls, and each lamp pearl comprises: LED luminophor 3, LED drive circuit 2, pedestal 1, fixed support 4, described LED luminophor 3 is positioned on LED drive circuit 2, and driving circuit 2 is fixed on pedestal 1, pedestal 1 is fixed on fixed support 4, and fixed support 4 is fixed on lamp pearl panel 5.As Fig. 2 be display screen of the present utility model with as shown in large-power LED light bead array drive circuit functional-block diagram, described LED drive circuit comprises and connecting in turn: Boundary-Type step-up type power factor correction circuit, active clamping forward converter, the spacing constant current width modulation of height drive light adjusting circuit.

Fig. 3 is the circuit theory diagrams of display screen of the present utility model with Boundary-Type step-up type power factor correction circuit in the large-power LED light bead array drive circuit; The electric main of input, after the full bridge rectifier rectification, obtains and inputs the sine voltage signal of synchronizeing with the form of electric resistance partial pressure; The feedback signal of output voltage after error amplifier therewith sine wave signal in multiplier, multiply each other, obtain sinusoidal reference signal, as the foundation of switch closing time; During switch conduction, inductive current rises, and current sense resistance is compared the inductor current signal of acquisition with sinusoidal wave reference voltage, switch cut-off when inductor current signal equals sinusoidal reference signal; After the switch cut-off, inductance starts to release energy, and now the auxiliary winding of inductance starts the zero current detecting, and when inductive current reduces to zero, the zero current circuit for detecting triggers flip-flop, and switch is conducting again, starts next cycle.

Fig. 4 is the circuit theory diagrams of display screen of the present utility model with active clamping forward converter in the large-power LED light bead array drive circuit; In transformer one side, main switch, auxiliary switch, clamping capacitance, resonant inductance are arranged, formed by two diodes, outputting inductance, output capacitance, loads in Circuit Fault on Secondary Transformer.Wherein main switch and auxiliary switch are MOSFETS, and resonant inductance equals outer coilloading and transformer primary side leakage inductance sum.

Fig. 5 is that display screen of the present utility model drives the circuit theory diagrams of light adjusting circuit with the spacing constant current width modulation of height in the large-power LED light bead array drive circuit.This circuit drives control integration circuit and light adjusting circuit to form by main switch, current transformer, current-limiting resistance, fly-wheel diode, energy storage inductor, light emitting diode module, output capacitance, flow control resistance, PWM.

The foregoing is only embodiment of the present utility model, be not limited to the utility model.The utility model can have various suitable changes and variation.All any modifications of doing, be equal to replacement, improvement etc., within all should being included in protection domain of the present utility model within spirit of the present utility model and principle.

Claims

1. display screen large-power LED light bead array is characterized in that:

Described LED lamp pearl array comprises 2 row 3 row totally six LED lamp pearls, each lamp pearl comprises: the LED luminophor, LED drive circuit, pedestal, fixed support, described LED luminous body position is on LED drive circuit, driving circuit is fixed on pedestal, pedestal is fixed on fixed support, fixed support is fixed on lamp pearl panel, and described LED drive circuit comprises in turn and to connect: Boundary-Type step-up type power factor correction circuit, active clamping forward converter, the spacing constant current width modulation of height drive light adjusting circuit.

2. display screen as claimed in claim 1 large-power LED light bead array is characterized in that:

Described active clamping forward converter structure is as follows: in transformer one side, main switch, auxiliary switch, clamping capacitance, resonant inductance are arranged, in Circuit Fault on Secondary Transformer, two diodes, outputting inductance, output capacitance, load are arranged; Wherein main switch and auxiliary switch are MOSFETS, and resonant inductance equals outer coilloading and transformer primary side leakage inductance sum.

3. display screen as claimed in claim 1 or 2 large-power LED light bead array is characterized in that:

The spacing constant current width modulation of described height drives light adjusting circuit to drive control integration circuit and light adjusting circuit to form by main switch, current transformer, current-limiting resistance, fly-wheel diode, energy storage inductor, light emitting diode module, output capacitance, flow control resistance, PWM.