CN203404671U

CN203404671U - Large-power LED lamp bead

Info

Publication number: CN203404671U
Application number: CN201320338125.6U
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: 2014-01-22
Anticipated expiration: 2023-06-13

Abstract

The utility model provides a large-power LED lamp bead, which comprises an LED luminous body, an LED drive circuit, a base and a mounting seat. The LED luminous body is arranged in the LED drive circuit. The drive circuit is fixed on the base. The base is fixed onto the mounting seat. According to the technical scheme of the utility model, the LED drive circuit comprises a boundary type boost power factor correcting circuit, an active clamp forward converter, and a high-low bias constant-current pulse-width-modulation-driven light-modulation circuit, wherein the boundary type boost power factor correcting circuit, the active clamp forward converter, and the high-low bias constant-current pulse-width-modulation-driven light-modulation circuit are sequentially connected together. According to the technical scheme of the utility model, the analysis on the light-emitting characteristics of a light-emitting diode (LED), with a liquid crystal display (LCD) backlight module as the application background thereof, shows that, the current control means is an optimum manner for the brightness adjustment of the LED. In order to realize a higher light-emitting efficiency and a better light-modulation effect, an LED-driven light-modulation circuit of a tertiary structure is adopted. Experiments show that, by means of the LED drive circuit, not only the power factor of the system is improved, but also the main wavelength of the LED and the shift in chromaticity coordinate are reduced. Therefore, the brightness of the LED is effectively controlled.

Description

Large-power LED light bead

Technical field

The utility model relates to Display Technique field, LED-backlit source, more specifically, relates to a kind of large-power LED light bead equipment.

Background technology

At present traditional along with social progress and the development of technology, the display device that the features 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.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.The leading panel vendor such as ，Yi Korea S Samsung and Japanese Sharp when various countries actively build 8.5 generation lines, 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 LED array can be made infinity in principle, 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 supports 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 cannot be made superhuge display device.

2, side entrance back structure

But because current LED brightness range is limit, LGP 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 cannot be made equally

Superhuge display device.

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

Utility model content

For the problems referred to above, the utility model provides large-power LED light bead, it is characterized in that: described LED lamp pearl comprises LED illuminator 3, LED drive circuit 2, pedestal 1, mount pad 4, described LED illuminator 3 is positioned on LED drive circuit 2, drive circuit 2 is fixed on pedestal 1, and pedestal 1 is fixed on mount pad 4.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 pulsewidth 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 fine definition, giant-screen.

Accompanying drawing explanation

By describing in more detail exemplary embodiment of the present utility model with reference to 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 cross-sectional view of the present utility model.

Fig. 2 is large-power LED light bead driving circuit principle block diagram of the present utility model;

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

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

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

The specific 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 cross-sectional view of the present utility model, described LED lamp pearl comprises LED illuminator 3, LED drive circuit 2, pedestal 1, mount pad 4, described LED illuminator 3 is positioned on LED drive circuit 2, drive circuit 2 is fixed on pedestal 1, and pedestal 1 is fixed on mount pad 4.If Fig. 2 is as shown in large-power LED light bead driving circuit principle block diagram of the present utility model, 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 pulsewidth modulation of height drive light adjusting circuit.

Fig. 3 is the circuit theory diagrams of Boundary-Type step-up type power factor correction circuit in large-power LED light bead drive circuit of the present utility model; The electric main of input, after 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 deadline; 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 switch cut-off, inductance starts to release energy, and now the auxiliary winding of inductance starts zero current detecting, and when inductive current reduces to zero, zero current circuit for detecting triggers flip-flop, and switch is conducting again, starts next cycle.

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

Fig. 5 is the circuit theory diagrams that in large-power LED light bead drive circuit of the present utility model, the spacing constant current pulsewidth modulation of height drives light adjusting 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. large-power LED light bead, is characterized in that:

Described LED lamp pearl comprises LED illuminator, LED drive circuit, pedestal, mount pad, described LED luminous body position is on LED drive circuit, drive circuit is fixed on pedestal, and pedestal is fixed on mount pad, 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 pulsewidth modulation of height drive light adjusting circuit.

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

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

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

The spacing constant current pulsewidth 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.