Supertex LED Driver Uses Closed-Loop System to Deliver Maximum LED Light Performance

It was reported from SUNNYVALE, CA on Feb 17 that supertex /quotes/comstock/15*!supx/quotes/nls/supx  (SUPX  25.70, +0.05, +0.19%) , a recognized leader in high voltage analog and mixed signal integrated circuits (ICs), today introduced the HV9963, a closed-loop LED driver IC with pulse width modulated (PWM) dimming capability designed to optimize LED performance and efficiency and extend LED life. The IC excels in DC/DC applications such as RGB or white LED backlighting, LCD TVs and monitors, and LED lamps for general lighting.

The HV9963 utilizes a closed-loop system to control the current going to the LED string, which is an active, real-time system that continuously monitors the LED current via sense resistors. The HV9963 includes a 1.0MHz transconductance amplifier with a tri-state output, which closes feedback loops in the sensing process and provides accurate current control. It can be synchronized in applications requiring multiple LED drivers to prevent the system sub-harmonic oscillations that are often associated with driving multiple driver schemes.

The HV9963 also features hiccup mode protection for both short- and open-circuit conditions, and a high PWM dimming ratio. The IC operates in a constant frequency mode for use in a variety of converter topologies such as buck, boost and SEPIC.

“The HV9963’s closed-loop system enables accurate line and load control of the LED current over its entire operating range,” states Ahmed Masood, Vice President of Marketing for Supertex. “This IC also includes controls that allow PWM dimming at very low duty cycles, resulting in a contrast ratio of up to 5,000:1.”

The HV9963 is available in a 16-lead SOIC package (HV9963NG-G). The part is RoHS compliant. Samples are available from stock. Lead-time for production quantities is 4-6 weeks ARO. Pricing is US$0.85 each for the HV9963NG-G in 1K quantities.

About Supertex Supertex, Inc. is a publicly held mixed signal semiconductor manufacturer, focused in high voltage analog and mixed signal products for use in the medical, LED lighting, imaging, industrial, and telecommunication industries.

The Main Challenge of LED Industry

In last article, we talk about that there’s a consensus that most of those barriers. They should be removed in the next 2-3 years. Impressive energy efficiency progress are announced on a regular basis by LED manufacturers and reliability is improving as engineers become aware of the challenges posed by the design of a flawlessly integrated LED luminaire (GE recently identified more than 100 possible failure mode in LED light engines).

Multiple standardization organization are working on defining and implementing testing and performance standards and communicating them to the public. Solid state lighting is progressing niche by niche.  More municipalities are testing LED streetlight and some have already committed to massive retrofits (200,000 street lights in Los Angeles). Adoption in commercial and retails lighting, while still low in volume is progressing fast (announcements from Wall Mart, Starbucks…). While we all have our eyes focused on residential applications, it’s important to realize that homes are the smallest segments (in term of lumens) compared to industrial, commercial and municipal lighting. However, for most, it remains the ultimate frontier.

But even this application now seems within reach and LED replacement bulbs might come to your home faster that you expected. Don’t rush yet though, as low quality products are still flooding the market and might create a negative initial perception of the technology, a risk that the industry is aware off and trying to control by working on performance standard (make sure you get products meeting or exceeding the Energy star criteria for solid state lighting). In Japan, the largest electronic manufacturers are making a strong push with quality products. Toshiba Lighting and Technology introduced a 60W equivalent replacement LED bulb for JPY9,000 in late 2008. The same product now goes for less than JPY4,000. Sharp launched similar offers and the price is now expected to reach  JPY2,000 in 2010. At this pace, most now expect the cost of LED replacement bulbs to reach the $10 for 1000 lumen target commonly accepted as the “magic” number that will trigger massive adoption by 2012.

In the US, Philips released the first LED bulb to participate to LPrize contest organized by the US Department Of Energy to reward the first 60W replacement LED bulb to meet aggressive performance targets.  A lot of credible light bulb replacements could be seen at the recent Strategies In Light conference exhibition floor and CREE is planning to release a retail version of its award winning LR6. The price point at which it will be released will send a strong signal to the industry.

Accelerated Growth of LED Industry

The LED industry has entered a period of accelerated growth driven by faster and broader adoption of the technology for large LCD TV.

After riding the cell phone keypads and LCD screen backlight wave during the previous decade, the industry is on for a spectacular growth thanks to large LCD backlight applications. While similar in essence to the smaller LCD screens, the larger displays found in laptops and large flat panel TVs were until recently more difficult to illuminate with LEDs because of their large surface. One must give credit to Sony and Lumileds, now a subsidiary of Philips, for pioneering the field in 2005. However, while delivering outstanding performances, the price of those LED backlit TVs were out of reach (>$10,000) for most consumers. A strong push by Apple, Dell and other brands allowed LEDs to start being adopted in laptops in 2007. In 2010, the adoption of LED for the segment should exceed 80%. But until 6-8 months ago, the industry consensus was that broad adoption of LEDs for large displays (20” and above) was still at least a couple years away. Samsung shook the industry in the second half of 2009 by bringing into the market a flurry of breakthrough products at affordable prices. Thanks to various engineering breakthrough and a strong marketing push (LED TVs anyone??), the unexpected success of the product put large LCD TV 2 years ahead of the initial roadmap and rescued the LED industry from what was going to be its first year ever of negative growth in 2009 (2001 was a flat year).

Since then, All TV manufacturers have jumped into the bandwagons, and LG, Sony, Sharp, Vizio, Toshiba all lined up an impressive series of new LED backlit LCD TV for 2010 with aggressive pricing. The cost of LED backlit TV remains marginally higher than “old fashion” cold cathode fluorescence lamp (CCFL) TV. However the price gap is shrinking and the consumers are falling for those ultra-slim TV with high contrast ratio and in some cases, improved color gamut and reduced motion blur. However, because of the engineering tradeoffs necessary to keep cost under controls however, not all the potential benefits of LED backlit TVs are offered on every set.  But, as technology improves, LED cost decrease and economy of scale become significant, the adoption rate of LEDs in LCD TV is expected to jump from 2-3% in 2009 to more than 20% in 2010 with the most optimistic forecasting 39 millions LED TV sets for the year. The adoption rate should further increase to 70% by 2013 and volumes exceed 150 millions. The exact impact on the LED industry is difficult to quantify though: because of the mix of panel size and the variety of design options (edge lit vs. backlit, white LEDs vs. RGB), estimating the exact number of LED chip per TV set is challenging (it varies from 250 to more than 1,000 on certain models). The one sure thing however, is that LCD TV will carry the LED industry through what analysts call it second growth cycle, possibly slightly restrained by tensions on the Sapphire substrate market and the ability of equipment manufacturers to deliver the record amount of MOCVD reactors to be shipped in 2010 and of the chip manufacturer to install and qualify them on time (it takes3 months to start production on a new reactors and in some cases another 4-6 months is needed get the chips from the new reactor validated by the final customer).

So what about the next big thing for LED: General Illumination? The main barriers to a broad and immediate adoption are still here. Those are essentially:
- Energy efficiency.
- Reliability.
- Color consistency and stability.
- Lack of standardization.
- Confusing supply chain.
- Upfront cost.

LED Makers Promise to Shake up Global Market

LEDs, once confined to the tiny red indicator lights on TV remote controls, have now grown to illuminate TV screens themselves and promise to shake up the global lighting market.

LED (light emitting diode) backlit TVs were heavily featured at the Consumer Electronics Show in Las Vegas this month, as manufacturers announced products intended to emulate the success seen by Samsung in 2009.

Samsung, which has 80 per cent of the US market for LED TVs, aims to quadruple global sales in 2010 to more than 10m.

But manufacturers such as LG, another Korean player, say Samsung will not have things all its own way as LED-backlit TVs become available at entry-level as well as premium prices. LG will offer cheaper edge-lit LED technology, which requires fewer arrays of diodes, on its entry-level TVs and full LED backlights on premium models.

LEDs have graduated from use in mobile phone screens to backlights for notebooks, PCs and now TVs and monitors.

They offer better brightness and contrast, energy savings and slimmer screens than those using the established cold cathode fluorescent lamps (CCFLs) now used for backlighting.

LED technology was first introduced in 1962, beginning with a low-intensity red light. Semiconductor-based diodes or valves produce light from the excitation of electrons as they are moved over a “light” bridge by a direct electrical current. LEDs differ from traditional incandescent light bulbs, which produce their light from heat generation.

Over the years, white LEDs have been developed by combining chips that produce different colours into a single package, or by adding a yellow phosphor layer. Improvements in light intensity and cost reductions are now resulting in wider adoption of LEDs.

Pete Moran of the DCM venture capital firm says LEDs have advantages such as longer life and greater efficiency compared with both incandescents and the energy-saving compact fluorescents with which consumers are currently replacing them.

As well as the green argument, there are manpower savings from LED’s longevity. Cities such as San Francisco, San Jose, New York and Minneapolis are testing LED street lamps that will not need regular bulb replacement by lighting crews. In retail, Walmart and Starbucks are replacing lighting in their US stores with LED bulbs to cut energy consumption.

But as big semiconductor makers such as Samsung and Micron begin to take an interest in the LED industry, it could eventually take on the same characteristics as the DRAM, or flash memory, industries, according to analyst Daniel Amir.

The LED industry will then become cyclical, with a period of oversupply as early as the second half of 2011, according to Lazard, although demand should still be growing at rates of 20 to 30 per cent a year.

Copyright The Financial Times Limited 2010. You may share using our article tools. Please don’t cut articles from FT.com and redistribute by email or post to the web.

Rockler Recalled LED light kits

Legal news for product liability attorneys. A voluntary recall of LED light kits was announced after discovery of defective wiring.

CPSC alerts product liability lawyers- Rockler Companies Inc. announced voluntary recall of LED light kits.

Washington, D.C.—Rockler Companies, Inc., of Medina, Minnesota and the U.S. Consumer Product Safety Commission (CPSC) have announced a voluntary recalled of LED light kits. Nearly 2,200 LED light kits were recalled on January 12, 2010, as reported by the CPSC.

The CPSC has urged consumers to stop using the recalled LED light kits immediately unless otherwise instructed after the discovery of defective wiring in the light kits. The defective wiring can cause the battery pack to overheat and explode, which poses a risk of burn and fire. At this time no injuries and/or instances have been reported. This recalled product is described as Rockler LED lights with either an interchangeable spotlight head, or a magnifying head. The recalled product models have stock numbers 26429 (spotlight or 27017 (magnifying). The stock numbers are printed on the products packaging. The LED light kits were sold at Rockler Woodworking and Hardware and other specialty stores across the country from March 2009 through October 2009 for the retail price of $60. All consumers who have purchased the product can contact Rockler Companies at (800) 260-9663 to receive a fee repair kit and installation instructions.

Nanosys Do Efforts to Improve LEDs

As we all know that in this struggling economy, businesses as well as the general populace are all struggling to do more with less. In the case of LED and nanotechnology, however, that may not be necessarily a bad thing.

Take for example the work showcased at CES by Nanosys, a company that has developed a method to add nanomaterials to blue LEDs that improves the appearance of LED lighting. Their efforts have created an LED light that combines the energy efficiency of a blue LED; with a nanotechnology layer that alters its blue appearance into a warm white light that is better than standard LED lighting.

The benefits of the added nanotech material not only means improving the quality of the emitted light for backlit LED displays
, but doing so while still maintaining a low power profile. Plus Nanosys claims, the process can be added to a company’s assembly line for electronic products without the need for major retooling.

So expect to see better looking LED lighting in the near future as Nanosys nanotechnology starts to appear in televisions and other lighting products beginning later this year.

The Future of LED Lighting Industry

Even better, the industry offers a superior product with an earth-first attitude. The LED light bulb, which use current passed through a diode to provide light, is in the midst of serious growth. Databeans, a leader in electronics market research, estimates that the global LED market will grow to $5.3 billion by the need of this year. An impressive figure by itself, this number is all the more striking when taken into account that very few consumers are using LEDs, as they are currently far more common in commercial applications.

The rate of growth is remarkable, but the fact that the size of the energy efficient light bulb industry is growing should come as a surprise to no one. These bulbs provide significant financial savings by reducing energy costs up to 75% compared to incandescent bulbs. Maintenance costs are also lowered due to a far longer life (up to 50 times longer than incandescent lamps. This also means less time spend climbing ladders, recycling bulbs, and dealing with outages. Other benefits of LED light bulbs include a much cooler operating temperature and more flexible color options.

The most important reason for the growth of the LED light bulb industry is that these bulbs have a much smaller environmental footprint. Less energy used due to an efficient product and less trash in our landfills due to a longer life and fewer replacements are both very compelling reasons for eco-conscious companies to make the shift today. LEDs are great as part of your commercial lighting plan, which should be developed with a lighting consultant or expert.

Many vendors offer affordable LED light bulbs. Where suppliers really differentiate themselves is in the level of expertise which they bring to the table. Companies such as Superior Lighting, Ft. Lauderdale’s energy efficient lighting experts, understand this entirely. Their wealth of knowledge enables them to work with their clients to develop cost-effective energy-efficient lighting plans for both commercial and residential applications. Anyone thinking about going green should give them a call today to see what they can do for you.

Superior Lighting’s, Ft. Lauderdale’s (South Florida) energy efficient lighting expert, mission is to help our customers choose the most energy efficient lighting. We lead the lighting industry by providing the best value in products and services to all of our customers, and we differentiate ourselves on the basis of our honesty and expertise.

Blowable LED Candle Lamp

Could you imagine that turn on or off lamps without switches but just a blow? Sure! Ok, I will introduce this kind of lamps following.

With so much of artificiality and heaps of tech substitutes around, any resemblance to natural stuff is refreshing. Candles were one of our resorts before Thomas Edison hatched the bulb, so these LED Blow On Off candles are here to remind you about the good old days.

The flames controls are just a Blow away. It has an edge over the usual candles as they turn off when you blow but this one will blow on. There is a master on/off switch at the bottom that helps your realize the blow controls.

A blue and yellow flame is what we have to choose from. I wonder why the makers didn’t think of introducing the VIBGYOR scheme here. No solar inputs here, 3 AAA batteries provide the necessary juice for as much as 300 hours. Bizarre, huh? They retail in the price bracket of $11.99 to $14.99.

This one surely joins the league of unconventional lighting devices with Elephant Lamp, the Candle Lamp Concept and the Rainbow LED Lamps.

LED Wind Turbine Light

Windmills have inspired Mathmos to come up with Wind turbine LED lights, and you can use these lights in your gardens or inside your own room for your personal leisure.

Wind turbines are the best eco-friendly sources of energy and in this day and age we definitely need more alternative, reliable and long lasting sources of energy. These lights function based on the same principle of windmills, and they light up as you blow on them.

So you can now enjoy a relaxed breezy evening and a nice dinner in your garden lit up with these LED lights for only $14.99 at ThinkGeek.com. They are also small enough to be mounted on your bedroom window too, if you fancy that! Some other eco-friendly lights and lamps that you can look at are the Spray Can lighting and Spark green energy lamp.

Sure! It is really cool. What is the application of this LED? I think it will be not widely used in our life but the idea is helpful to our future design.

Energy Saving with LED Fluorescent Lights

There are millions of general service fluorescent tubes in the market place today, until recently these were considered the most energy efficient lighting solution available. The downside to this for of lighting is that each tube contains a small amount of mercury vapour, a toxic heavy metal. This can provide not just a health risk when the tubes are broken, but can also accumulate in landfills before entering the water table or causing further pollution.

Fluorescent lamps use electricity to excite mercury vapour inside the glass tube and always require a ballast to regulate the flow of power through the lamp. A starter is in the circuit to heat the contact ends of the tube that ionizes the mercury vapour creating UV light. The inside of the tube is coated with a phosphor material that glows when exposed to the UV light produced by the mercury inside the fluorescent tube.

Recent developments in SMD (Surface Mount Diode) LED technology have now meant that LED based fluorescent tubes are now a reality. LEDs are a more efficient form of lighting product consisting of small chips of conductive material that release light when a current is applied to them. They contain no filaments and can produce up to 25 times more light per watt than conventional light bulbs.

LEDs require far less energy in their manufacture than fluorescent tubes, and only 3% of the energy they will consume over their life expectancy is consumed in their manufacture, and they are also produced from non toxic materials. The tubes are made from polycarbonate, a material that is more robust and durable than glass, so accidents will not require special cleanup procedures.

While LED technology is more expensive than existing fluorescents at face value, they will last up to 10 times as long, while consuming 65% less energy. In most general purpose lighting applications they additional cost of the LED technology will more than pay for itself within the first 18 months.

The only drawback is the tighter beam angle of the LEDs, while some tubes are manufactured from a polycarbonate light diffusing material, others have a narrow focus which may not be suitable for replacing existing tubes. Many fluorescent fixtures are designed with reflectors that help to distribute the light from the tubes evenly in their intended environment. This is a problem similar to what was faced when compact fluorescents began replacing incandescent light bulbs, this is a problem that will soon be overcome and allow faster adoption of this emerging lighting technology.