Liu Xuechao, a senior technology market development engineer at Texas Instruments, said that the development of LED technology requires the development of driving technology. Today's LED market is 100 million US dollars, and will expand more than 10 times in the next 3 to 5 years.
For the Chinese market, National Semiconductor Asia Pacific Marketing Manager Li Zhiyuan quoted iSuppli's forecast for China's LED driver Ic market. In the global economy and electronics industry sinking recession, China's LED driver Ic market only increased by 1% in 2009, from 2008 The $115.3 million rose to $1.16 billion. However, the growth rate in 2010 will accelerate to 9.6%, and the scale will reach 127.7 million US dollars. The LED market in China is expected to reach $139 million in 2013.
Looking forward to 2010. As the global economy gradually recovers, the LED driver IC market for automobiles and communications is expected to stabilize in 2009, and the industrial/lighting market also has a two-digit growth space. For information and consumer electronics markets, There will be leapfrog growth. It is estimated that the global LED driver Ic market will expand to 3.41 billion in 2010, compared with 2.70 billion in 2009, with a growth rate of 26.0%.
However, the requirements for LED drive power are also increasing. According to Bill Weiss, senior product manager at pI. The technical development trend and characteristics of LED driver Ic are: high reliability, high efficiency, high power factor, dimming and small size.
Li Shengtai, director of development of OzMicro Technology (China) Co., Ltd., introduced the technical characteristics of LED drivers. He said that the focus of many manufacturers is: 1. The improvement of LED luminous efficiency: 2. The thermal management of LED modules: good heat treatment . Whether it is good for LED life or color rendering; 3. Conversion efficiency: Based on the purpose of energy saving and carbon reduction, whether it can effectively utilize the power provided by public power plants - the conversion of power factor is also the key direction One: 4. Product reliability: more in the material options and circuit design: 5. LED backlight: In technology, the main challenges faced by using LED as backlight: current matching in multiple LED strings . Including power consumption, protection circuits, noise during dimming (Audiblenoiseduringdimming).
The following is a brief introduction to the technical market for LED lighting, backlighting and LEDTV.
LED lighting
LED lighting market is full of potential
Liu Xuechao of Texas Instruments said that LED lighting is developing very rapidly, with an annual growth rate of more than 60%. With the continuous improvement of LED luminous efficiency, packaging technology continues to improve, driving land energy and life expectancy, LED lighting technology will gradually gradually in the next five years. Enter thousands of households.
02Iviicro Li Shengtai said that under the trend of increasing environmental protection issues in various countries around the world, the LED lighting industry will play a very important role. Its main applications are high-power products such as indoor and outdoor lighting and street lights. It is reported that in 2009, the global lighting market was about 121.9 billion US dollars, and LED only accounted for 0.5%, which shows that its future potential is considerable. Among them, the market size in the Asia-Pacific region is the largest, accounting for 33.7% of the world's total: 30.1% in North America and 27.4% in Europe: however. Discuss with application products. Outdoor lighting accounts for about 12%, which has considerable room for growth, especially in the Chinese market, which accounts for 38% of the world's outdoor lighting. In addition, the part that deserves attention is that the streetlight application, which is directly and quickly affected by government policies and promotion, is expected to become the first great growth in the lighting industry: it is estimated that in Europe and the United States, the global trend can be achieved in 2010. The level of 4.5 million LED street lights: and in the footsteps of international energy conservation and carbon reduction, once the standard specifications of street lamps are popular, the Chinese market is expected to occupy more than 50% of the world.
From the perspective of LED brightness, the light output of high-power LEDs has reached an important milestone of 100 lumens / w, while some manufacturers claim to have reached 120 lumens / W in the laboratory. Tony Armstrong, director of power products marketing, Linear Technology That said, this means that, in terms of efficiency, LEDs now exceed CFL (80 lumens/w). However, according to further predictions, by 2012. The LED will reach an output of 150 lumens/W. In addition, the current focus is on "green", unlike CFL, which does not contain any harmful materials.
From the perspective of LED cost, the cost of LED lighting has been rapidly declining. In the past 12 months, the price of dedicated white light diodes (many of which have been used by LED bulbs and accounted for most of their cost) has dropped from around $8 a few years ago to $1.50. Many LED industry analysts predict that in the coming year, the price of LED lamps replacing incandescent lamps will reach acceptable levels for consumers. Some LED manufacturers claim to have designed a light-emitting chip that can drive LED lights, and that can make LED lights produce light comparable to 75W incandescent lamps (75W incandescent lamps are commonly used in American homes). In order to output light of this magnitude, such LED chips typically require about 12 W of power.
Lighting LED Driver IC Features
Yan Zhongguang, Marketing Director of Jingfeng Mingyuan Semiconductor Co., Ltd., has an amazing workmanship: At present, common LED light source driver ICs are borrowed from general-purpose power ICs. There are few driver ICs designed for LED light sources. Many companies are designing them. Among them, it is expected that there will be many cities in the middle of 2010. At present, LED) light source driven resistor-resistance step-down low-cost solution is unsafe. CCR can only drive LEDs below 0.5w, and LDo uses a voltage-stabilized method to drive the life of LED light sources: DC/DC-constant current source and The AC/DC-constant current source is probably one of the most ideal solutions currently known.
Throughout the driving technology of DCLED light source, there are three types of driver ICs will be the development trend: one is DC/DCBuck produced by high voltage process, Vin is wide to DC60~100V. The constant current accuracy is 1%. It will be able to meet all DC LED lamp drivers. The need to meet the needs of LED light source multiple series and technology: The second category is Ac/DCI LED lamps require a simple application circuit, low application cost, high efficiency resonant half bridge capable of over EMI, CE, UL (LLC The +PFC topology drives Ic; the third is power factor correction (PFC) + pulse width control (pwM) two average current mode controllers to form a new AC / Dc driver Ic. They will appear in the new generation of LED lamps Its strong vitality to fully exploit the advantages of zero voltage switching topology (ZVS), and to meet the increasing requirements of LED lamps for PFC (power factor correction), and to require at lower power levels (such as <50w) Increased efficiency >90%. Wide voltage input, short circuit and over power protection, open circuit protection, and lower total harmonic distortion (THD) are basic requirements.
Linear Technology's Tony Armstrong also has similar views. He pointed out that one of the key features of LED driver Ic today is that it must be able to fully dim the LED. Because the LED is driven with a constant current, its DC current value is proportional to the brightness of the LED, so to change the brightness of the LED, there are two ways to dim the LED current. The first is analog dimming by reducing the constant LED current value. Proportionally reduce the LEDDC current value. Reducing the LED current may result in a change in the color of the LED or an inaccurate control of the LED current. The second is digital dimming or PWM dimming. PWM dimming switches the on and off of the LED at a frequency equal to or higher than 100 Hz, and is switched at such a frequency that the human eye is not aware of. The PWM dimming duty cycle is proportional to the LED brightness, while the LED current at turn-on remains the same value (as set by the LED driver Ic), thereby maintaining a constant LED color at high dimming ratios.
In some applications, this PWM dimming method can be used to achieve a dimming ratio of up to 5000:1.
Allan Lin, manager of LED lighting at Diodes, also believes that the future development of LED driver technology is reflected in two aspects. He said, first, off-line high power factor correction dimmable LED driver can replace halogen, incandescent and fluorescent lamps; . LED drivers can effectively replace low voltage halogen lamps. Both of these applications require electrical and thermal protection for the LEDs to increase their durability. Other trends include optimizing drivers to provide optimal performance, not maximizing current.
China is a global manufacturer. The manufacturing cost of LED driver technology and the overall BOM (bill of materials) cost are critical. To this end, Diodes is dedicated to the development of cost-effective LED driver technology.
LEDTV
After Samsung successfully brought up the LEDTV topic, the trend of LED backlighting for TV has become one of the most concerned focuses. It is estimated that its penetration rate will climb to 10%-15%.02 in 2010, Micro Company Li Shengtai said In the past, due to color rendering and contrast considerations, direct-type backlight (DirectType) has always been the main axis of LEDTV development direction: However, driven by the advantages of cost and thin design, edgeTyVe backlights have become mainstream, accounting for At least 93% of all LEDTv models. And focus on TV size above 40 inches: Therefore, for the future prospects of LCD TVs, LEDTV will be one of the development spindles in 2010. LEDTV products are positioned in the high-end market at this stage, and LED backlights are used in the rise of LCD TVs. One of the main tests is the price difference between them and cCFL backlights: the development of side-lit backlights has indeed greatly narrowed the distance between the two. The challenge remains; according to the (BPSemi) marketing director, the price difference between the 40-inch and 46-inch LED-backlit LCD TV panels in the third quarter of 2009 and the same size CCFL is about 35%. It is expected to be available in the first quarter of 2010. Nearly 30% of the gap. In addition, a TV set is dozens of times more expensive than a notebook computer (NB); in other words, the development of LEDTV is also limited by the development of LED capacity and the price limit. If the supply of LED chips continues to be soothed in the future, it can help. When the sales price is closer to the acceptable range for consumers, LEDTV will have the opportunity to grow faster than the current development of LEDNB.
Backlight
Intersil believes that advanced applications such as TFT (Thin Film Transistor) backlights require additional features including PWM dimming, DC dimming, local dimming, PWM-Dc dimming, and direct PWM dimming. IntersiI claims that its high-power multi-channel LED driver has excellent dimming linearity and can accurately perform 0.4%-100% dimming with a matching ratio of ±1%.
Fairway Semiconductor Technology Marketing Manager WayneSeto said. In China and other parts of the world, mobile phone LED driver circuits are moving from a charge pump architecture to a series boost architecture. Because the latter is not only more efficient, but also drives more LBDs to support larger display screens. As smartphones and larger LED displays continue to grow in popularity, the need to drive seven or more LEDs is widespread. The best method is to drive the LEDs in series to make the brightness of each LED the same; and because the charge pump drives the LEDs in parallel, no matter how small the screen is, the current (ie brightness) of the parallel channel will have some Some differences. From a design layout perspective of more than seven LEDs, if a charge pump LED driver is used, the layout of the PCB (printed circuit board) can be more complicated: it is much simpler to use a series boost LED driver. For cost-conscious phones, linear LED drivers are a development direction, with simple circuitry and easy integration into the design. However, charge pump solutions will continue to be widely used in cost-sensitive product areas and low-end mobile phones.
Some LED driver supplier features and products
Linear Technology's high-brightness LED driver ICs have the following typical features: wide input/output voltage range: up to IOOV; high efficiency conversion: up to 95%: tightly regulated LED current matching: less than 2% over temperature . For example, the LT3743 is a synchronous step-down DC/Dc converter designed to provide constant current to drive high current LEDs. The new LT3754 solves the problem of driving white LEDs encountered when white LEDs are used to backlight large flat panel displays. It can be used in HDTVs with flat panel displays of 26 inches or larger.
· BPSemi's LED lamp driver Ic uses advanced technology for local oscillation frequency jitter. It greatly simplifies the anti-EMI part of the application circuit. Effectively reduce application costs and PCB area. Typical applications such as the BP1360/1 require only five components and are widely used in DC LED lighting and LCD-TV side backlighting. BP2808 adopts constant current compensation technology and current control patent design to provide constant supply current for LED light source. The output constant current accuracy is better than 2% in AC85~305v input range. It has been successfully applied to the indoor lighting of Shanghai Pavilion at Shanghai World Expo.
PI provides an efficient LED driver power IC: low no-load power consumption and good standby power performance in all integrated solutions: a proven reliable power conversion solution; a highly integrated solution, including The low number of components, low cost of eBOM, easy to design and pass certification: global real-time local technical support. The three LED driver Ic solutions from PI are available for download from the web. For example, a 150W power factor corrected LLC power supply designed using HiperPLC (PLCSIOPG) is suitable for high power LED street lights.
Oiodes acquired Zetex in 2008. Also mastered the advanced BuckLED driver technology. Diodes' three LED driver technologies include: Diodes' solution is very streamlined: only 4 external components, performance is over 90%; with high power density leaded package, TSOT23-5 package is lower than the competition The thermal resistance can be used in the latest generation of small circuit board LEDs that replace traditional lamps; with a complete solution: with discrete Ic integrated circuit capability, it can simultaneously provide LED drivers and rectifier components required in LED lighting solutions.
Texas Instruments has a range of LED driver solutions such as high power DC/DC boost LED drivers (TPS61500), high voltage DC/DC boost converters (TPS61175), and step-down DC/DC converters (TPS62110) Power management chip. These three products support input voltages up to 18V and have a small voltage reference to help improve LED circuit design. In addition, these low-energy products have a variety of functions and can be widely used in various LED applications such as signage, ambient lighting, office lighting, general lighting, medical and sensors.
Intersil has a range of LED-driven Ic product lines for a variety of applications, including automotive: high-end notebooks, POS displays and display backlights: Handheld products: general lighting systems. LED drivers can be configured as inductive white LED drivers for parallel LEDs or inductor-based white LED drivers for LEDs in series. Topologies include boost regulator LED drivers, buck regulator LEDs Drive, and buck-boost LED driver. For these applications. The ISL97671.81 series can efficiently drive 72pc (6-channel version) and 48pc (4-channel version) low-power LEDs in a wide range of meat.
National Semiconductor (NS) is the world's largest supplier of LED drivers in z006, with a market share of more than 14%. The company has a range of high-pressure product processes, defined in the 100V range.
The advantages of this high-voltage application include high efficiency and the ability to drive multiple strings of LEDs (up to 16 LEDs) for automotive, industrial lighting, and architectural lighting. In February 2009, NS introduced a new off-line constant current controller, the LM3445, which has the advantage of supporting traditional in-wall dimmers with tri-directional triac (TRL&C) forward or reverse phase control. .
Fairchild Semiconductor will focus on developing boost technology, as well as improving efficiency and functionality, and reducing the design difficulty of customers. Fairchild's strength in LED drive technology is to understand the customer's needs and applications to develop the best possible lighting solution.
The O2Micro solution addresses overheating and improved performance of LED clusters. In order to overcome the problem that the LED street light group battery life is too short and the LED light group is overheated in the market today. O2Micro pioneered the development of CoolDriverCircuit (OZ9986A). For 40~200W street light applications. Provide LED light group with good color rendering and color uniformity, and with its superior performance to achieve energy saving and low carbon effect. In LED backlight applications, O2Micro offers a non-TRICA three-stage dimming in the dimming mode, taking into account the cost f without rerouting or adding dimming switches.
Led Ball String Light
Best decoration for Christmas tree, outdoor trees, porch, around the patio table umbrella, Xmas, wedding, birthday party, outside, indoor.
Each string lights has a socket that can be connected to another string lights for infinite extension .Fairy lights with soft wire is very flexible to hang in kids bedroom,tent,etc.
Waterproof IP67, Non-friable ,not overheat, high voltage protection, cool to the touch.
The bulbs are each one color a piece, which I didn't know when I bought this, but I'm alright with that. They're cute, the frosted white globe over the LED bulb is nice. The colors, in order, are Blue, Orange (or dark yellow), Green, and Red, like you might find on traditional multicolor lights. The picture looks like there's purple or teal lights, but that's not true. The remote came with a battery, which was cool. The length stretches over my entire porch, exactly, which was a great surprise.
Led Ball String Light
Led String Lights Outdoor,Cotton Ball String Lights,Cotton Ball Fairy Lights,Cotton Ball Fairy Lights
Dongguan Xingyong Indusrtial Co,Ltd , http://www.xingyongled.com