At the Consumer Electronics Show (CES 2013) in Las Vegas, USA, which ended not long ago, Marvell, together with several partners, launched a number of leading products with the theme of “smart home” series products. As a more environmentally friendly and intelligent lighting method, LED lighting plays an important role in the “smart home”. Not only that, but in the field of commercial lighting, the popularity of LED lighting is also accelerating. Taking stock of the LED lighting market in 2012, Marvell, which was dubbed the “dark horse” by industry insiders, stood out among many LED driver solution providers and attracted widespread attention.
A few days ago, Mr. Lance Zheng, technical marketing director of Marvell’s Green Technology Product, made a special trip from the United States to China to attend the “2013 Industry and Technology Media Seminar” hosted by Yiweixun Information Consulting, and shared his views on the LED lighting market in the next few years. development trends and the direction of innovation (Figure 1).
picture1. MarvellThe company participates in“2013Industry and Technology Media Symposium“LEDThematic presentations and presentations.
ledThe development trend of lighting market
At present, the division strategy of Marvell LED lighting market is indoor lighting and commercial lighting. Lance made three predictions on the development trend of the LED indoor lighting market: First, thanks to the continuous decline in the price of LED lamps, LED lighting will enter an explosive growth stage in 2014-2015. Second, the entire market will move from non-dimming to dimming. Finally, wireless dimmable LED lights appear.
“In 2012, the cost of LED lamps continued to drop. In the US market, the price of mainstream 60W dimmable LED bulbs has dropped from $40/unit in 2011 to $20/unit, and will drop to $10/unit in 2013, and by 2015 It is expected to reach the replacement critical price of $5 per unit in 2014. So 2013 will be a critical year for this market, and the entire indoor lighting market will enter an explosive growth stage in 2014-2015.” Lance said.
He also pointed out that the difference in cost between non-dimmable and dimmable bulbs is getting smaller and the main cost difference is driving. For example, the cost difference between dimming and non-dimming of Marvell’s driving solution is only 20%, so this has driven the LED lighting market to switch to dimming. In the United States, all mainstream retail channels have turned to dimming solutions. “Last year, Philips launched the smart lighting system Hue. Although the price is very high, the market has responded very well. The smart lighting system will be further developed in 2013. “
As for the development trend of the LED commercial lighting market, Lance pointed out: First, the popularization of the industry is accelerating, such as shopping malls, hotels, retail, and outdoor installations using LED lights are increasing. With LED lighting, the commercial payback period for Cree’s latest LED lighting fixtures has been shortened to about a year.”
Second, based on DALI (Digital AddressableDimminginterface) standard digital dimming is also beginning to gain popularity in commercial lighting. DALI, which originated in Europe 10 years ago, is now gaining popularity and accelerating growth, has gained a firm foothold in the LED field, and is moving from Europe to Asia. It targets LED-specific functions, not just dimming, but also toning.
ledLighting to the popularization of the three“stumbling block“
Even though the price of LED bulbs is falling, LED lighting is still expensive for the average consumer. The cost remains high, and the volume of the LED drive circuit is too large, which has become the first “stumbling block” for LED lighting to go to the public.
As shown in Figure 2 below, the cost of LED bulbs to replace dimmable A19 60W bulbs is currently around $7-8. Among them, the cost of LED light source and drive accounts for the first and second place in the cost of the entire LED bulb. The good news is that the price of LED light sources has dropped a lot last year, but because the LED driver circuit technology has not been greatly innovated in the past, the cost of LED bulbs has remained high.
Figure 2. The cost of LED light sources and drivers account for the first and second largest LED bulb costs.
The size of the LED driver circuit is also a problem. Japan is one of the countries with the largest consumption of LED lighting, and its most popular bulb, the E-17, is very small. There are also very popular GU10 bulbs in Europe, which are also very small in size. Due to the limited space and the requirement of LED heat dissipation, it is very difficult to put the LED driver circuit into a small bulb such as E-17 or GU10.
The second “stumbling block” for LED lighting to the public is the compatibility issue with the existing lighting architecture. The most important thing here is the thyristor dimmer. There is no uniform standard for the inner workings of the various dimmers on the market. So, when LED driver electronics are put into LED bulbs, it is difficult to be compatible with various dimmers.
“Everyone knows that thyristor dimming is a very old technology, and it is mainly used for incandescent lamps. When ordinary consumers go to buy, they do not know how to replace the dimmer that is matched with it. Therefore, when you use LEDs When the bulbs are replaced by incandescent bulbs, performance will be affected. For example, when you install LED bulbs, you will find that when you turn it down to the lowest, it is not that low, and may flicker, and even worse when you turn it down to When the light source is at its lowest, it can’t start again. This brings great inconvenience to consumers.” Lance further pointed out.
The third “stumbling block” for LED lighting to the public is the will of consumers. It is said that LED can save energy and electricity bills, but only by launching different products can consumers’ desire to buy be stimulated. “Consumer expectations are high. After all, an incandescent bulb costs less than 50 cents, and an LED bulb is $10, so consumers have high expectations for added value, just like when Apple’s iPhone was launched. And Marvell The driving solution of the OLED can not only dim the light, but also color the color, if this additional value is provided to consumers, it will make them feel that it is worth buying!” Lance said.
ledThe key to popularization of lighting isledInnovations that drive technology
In the face of the above-mentioned challenges in the popularization of LED lighting, what are the countermeasures?
“We believe that LED driver electronics play the most important role in the commercialization of LED lighting. There are three reasons: first, LED driver technology is a key technology to ensure compatibility with existing lighting systems; second, LED lighting The cost of LED lighting is also very important (LED driving cost ranks second in the entire LED lighting cost); third, can it improve the user’s experience?” Lance pointed out.
Innovation 1: The digital-analog hybrid architecture can easily achieve the best dimming effect in the industry
Since the key to the popularization of LED lighting lies in the innovation of LED drive technology, then let’s take a look at what Marvell has done in this regard?
The digital-analog hybrid architecture is one of Marvell’s important innovations in LED drive technology. The so-called hybrid architecture means that each chip has a DSP core that can run algorithms. In addition to the DSP core, there is an OTP inside the chip, and the memory is programmable. The program does not need to be written by the user, but there is a development tool in which all the algorithms are solidified. With this OTP, the dimming curve of the driver chip can be adjusted. Another key point is that, unlike running the algorithm on a microcontroller, this does not require software development.
Take Marvell’s single-stage LED driver IC 88EM8183 launched last year as an example, it adopts Marvell’s unique mixed-signal architecture and advanced dimming control technology, and has dozens of patented technologies in algorithm and architecture; 88EM8183 can be programmed OTP and change The peripheral resistor is used to adjust the dimming curve. Deep dimming down to 1% LED current is smoothly achieved, compared to 10% to 20% dimming typically achieved by comparable LED driver solutions. With dimming at this magnitude, the human eye does not perceive a large change in light intensity, so the 88EM8183 significantly improves performance. It is the industry’s best dimming and cost-effective solution, with dimming efficiency up to 90%, high power factor (up to 0.99), and low total harmonic distortion (less than 15%).
The 88EM8183 is also compatible with most (TRIAC) wall dimmers, whether front-cut, rear-cut dimmers, or digital dimmers. The compatibility of its dimmers can reach 90%, while among competitors, it is close to 70% to 80%, and generally below 60%.
In particular, the 88EM8183 is also able to provide a wide range of output power platforms, and provides customer dimming and non-dimming, high voltage and low voltage unified platform. Commercial downlights based on the 88EM8183 have also been introduced to the market.
Figure 3 below shows another example of the application of the Marvell digital-analog hybrid architecture. This is a dual-string smart LED driver solution based on Marvell 88EM8801. The application of this solution can realize the adjustment of color temperature, high color rendering index, high energy efficiency, and can provide the best lighting quality close to incandescent lamps.
picture3. based onMarvellDual-channel digital-analog hybrid architectureleddriver implementedDouble string intelligenceledScheme block diagram.
Innovation 2: Smaller size, lowerBOMcost, more efficientBuck-boostNon-isolated solution
As mentioned earlier, in order to help OEMs and ODMs adapt to various form factors of LED lamps, such as A19, PAR, BR, E17, GU10 and Candle, without compromising dimming performance, the LED driver circuit board area is required to be as small as possible . By adopting Marvell’s new mixed-signal architecture and signal processing technology, and integrating as many analog devices as possible into the LED driver chip, the 88EM8183 can reduce the number of components required for the LED driver power supply by more than half, thereby greatly reducing the total number of required power supply volume.
In particular, it should be mentioned that, in addition to the Fly-back topology, the 88EM8183 can also support the Buck-boost topology, which is a non-isolated driver solution. The driver circuit size can be smaller and the BOM cost is higher than the Fly-back topology. much lower, and the drive efficiency is much higher.
“We recommend customers to use a non-isolated solution for high voltage and low current LED loads, so that the driving efficiency will be maximized.” Lance emphasized, “The 88EM8183 non-isolated solution can be directly used in very small standard bulbs such as GU10, Candle and EE17. Supporting these small-sized light bulbs is an extension application that is superior to other solutions on the market.” As we all know, GU10 and Candle are the most mainstream LED light bulbs with the largest shipments, and they are also delayed by major OEMs and ODMs. The trickiest product for the right solution.
Marvell currently provides a complete board reference design for the 88EM8183 non-isolated driver solution, which supports a wide range of output range applications, and is very easy to introduce into production, helping customers achieve very low PPM (as shown in Figure 4 below).
picture4 Marvellprovide based on88EM8183A complete board reference design for a non-isolated drive scheme.
Lance pointed out: “The Buck-boost non-isolation solution we just launched this year can be said to be the highest performance and lowest cost solution in the industry, with an average driving cost of 20-40% lower than that of competitors.”
Innovation three: inledAdd intelligent network control to the driver
One of Marvell’s co-founders, Ms. Dai Weili, said at CES 2013 that Marvell will further exert its strong integration strength in 2013 to provide consumers with a happy and connected life. The interconnection is the key here, and only adding the network control function to the LED driver can realize intelligent lighting in the true sense.
Based on the world’s first dual-channel smart LED driver chip 88EM8801 mentioned above, Marvell developed a unique smart driver architecture (Smart LED Driver) in the industry in 2012. Specifically, the benefit is that different configuration schemes can be selected.
picture5. MarvellintelligentledDriver Architecture and Reference Design
Lance imagined several applications in this media seminar: “LED light bulbs are already energy-saving, and they will be more energy-saving after adding control. For example, if you work late today, you can use your mobile phone to turn off the lights in your home, and before you get home, you can turn off the lights. Turning on again after 5 minutes is not only energy-saving, but also very convenient. In the United States, there is another feature. When the whole family is on vacation, they can turn on the lights when they are afraid of thieves coming to the door, which can prevent thieves from visiting to a certain extent.”
“Because there are many different control solutions on the market (Marvell has them all). However, customer needs will be different, so we have introduced this architecture to realize the compatibility and replacement of different control solutions by replacing the control module with unified interface.” Lance further pointed out.
Based on this architecture, Marvell designed the DALI control platform. As shown in Figure 9 below. Marvell DALI software supports the latest version of the DALI standard. DALI endpoint stack provides configuration, group scheduling, scene management and integrates with Marvell 88EM8801 to provide various lighting control functions including on/off control, deep digital dimming, CCT control, temperature compensation, correction, lighting fixture monitoring and energy consumption estimate.In addition, the DALI control architecture enables control of the Web Serve-based management user interface
picture6. MarvellSmart Lighting Platform-DALI(commercial lighting).
For the indoor lighting platform, “Marvell plans to launch a solution based on the Zigbee Light Link (ZLL) protocol standard in the second half of this year. As a low-power, low-cost technology, it will be used in smart home-related products such as the Marvell LED lighting platform. will be applied well,” Lance said.
picture7. MarvellSmart Lighting Platform——ZigBee(Indoor lighting).
Lance concluded at the end of his speech: “Since we launched the first deep dimming driver chip last year, the market feedback has been very good, and mainstream lighting companies have either already mass-produced or are preparing for mass production. The Chinese market is very important to Marvell. Because 90% of the entire LED lighting industry is in China. We will also continue to invest support resources to help promote the popularization of LED lighting and help the growth of China’s LED lighting industry.”