Three technologies accelerate LED lighting into the market

At present, the division strategy of Marvell LED lighting market is indoor lighting and commercial lighting. Lance put forward three predictions on the development trend of LED indoor lighting market: First, LED lighting will enter the explosive growth phase from 2014 to 2015 due to the continuous decline in the prices of LED lamps. Second, the entire market will shift from non-dimming to dimming. Finally, wireless dimmable LED lights appear.

“The cost of LED lamps continued to decline in 2012. In the US market, the price of mainstream 60W dimmable LED light bulbs has fallen from $40/2011 to $20/$ only, and in 2013 it will also drop to $10/$, and by 2015, The year is expected to reach an alternative critical price of $5/only, so 2013 will be a key year for this market, and the entire indoor lighting market will enter an explosive growth phase from 2014 to 2015,” said Lance.

He also pointed out that the cost difference between non-dimmable bulbs and dimming bulbs is becoming smaller and smaller, and the main cost difference is drive. For example, the difference between the dimming and non-dimming costs of Marvell's drive scheme is only 20%, so this has driven the LED lighting market toward dimming. In the United States, all mainstream retail channels have turned to dimming solutions. "Last year, Philips introduced the intelligent lighting system Hue. Although the price is very high, the market's response is very good. The smart lighting system will be further developed in 2013. ”

As for the development trend of the LED commercial lighting market, Lance pointed out that: First, the popularity of the industry is accelerating, such as the use of LED lights in shopping malls, hotels, retail, outdoor devices are increasing, "For example, the United States Wal-Mart supermarket has been comprehensive With LED lighting, the commercial return cycle for Cree's latest LED lighting fixtures has been shortened to around 1 year."

Second, digital dimming based on the DALI (Digital Addressable Dimming Interface) standard has also begun to gain popularity in commercial lighting. DALI originated in Europe 10 years ago, and now it is gaining popularity and accelerating growth. It has already established a firm foothold in the LED field and has moved from Europe to Asia. It targets LED-specific functions, not just dimming, but also color correction.

LED lighting to the popularity of the three "stumbling block"

Although the price of LED bulbs is declining, LED lighting is still expensive for the average consumer. The cost remains high, and the LED drive circuit is too large to become the first “stumbling block” for LED lighting to the public.

As shown in Figure 1 below, the cost of replacing the LED bulb of the dimmable A19 60W bulb is currently around $7-8. The cost of the LED light source and driver 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 fell a lot last year, but since the LED drive circuit technology has not been greatly improved in the past, the cost of LED light bulbs has remained high.

Figure 1: The cost of the LED light source and driver accounts for the first and second place in the cost of the entire LED bulb. The size of the LED driver circuit is also a problem. Japan is one of the largest consumers of LED lighting, and its most popular bulb E-17 is very small. There is also a GU10 bulb that is very hot in Europe and is also very small. Confined to the limited space and the requirement for LED heat dissipation, it is very difficult to put the LED drive circuit into a small bulb such as E-17 or GU10.

The second “stumbling block” where LED lighting goes to the public is the compatibility issue with existing lighting architectures. The most important thing here is the thyristor dimmer. There are no uniform standards in the working principle of the various dimmers on the market. Therefore, it is difficult to be compatible with various dimmers when putting the LED driving electrons into the LED bulb.

“Everybody knows that SCR dimming is a very old technology. It is mainly used for incandescent lamps. When consumers buy it, they don’t know how to replace the dimmer they matched with it. So when you use LED When light bulbs replace incandescent light bulbs, performance will have an impact, for example, when you have an LED light bulb, you will find that it is not that low, it may flicker, and it may even worse When the light source is at its lowest, it will not start again. This will cause great inconvenience to consumers," Lance further pointed out.

The third “stumbling block” of LED lighting to the public is the will of consumers. Said that LED can save energy, save electricity, but only the introduction of different products can stimulate the desire of consumers to buy. “Consumer expectations are high. After all, an incandescent lamp costs less than 50 cents, and LED bulbs are $10, so consumers’ expectations for added value are high, just as when the Apple iPhone was launched. Marvell The driver scheme is not only able to dim, but also to color, if the additional value to the consumer, it will make them think the value of the purchase!" Lance said.

The key to the popularity of LED lighting lies in the LED drive technology innovation faced with many challenges in the above-mentioned LED lighting popularization process, what is the countermeasure?

“We believe that LED-driven electronics plays the most important role in the commercialization of the entire LED lighting business. There are three reasons: First, LED drive technology is a key technology to ensure compatibility with existing lighting systems; Second, LED lighting The cost is also very important (LED drive cost ranks second in the cost of the entire LED lighting); Third, whether it can enhance the user's experience?” Lance pointed out.

Innovation 1: digital-analog hybrid architecture can easily achieve the industry's best dimming effect Since the key to the popularity of LED lighting lies in LED drive technology innovation, then let's take a look at what Marvell has done in this area.

The digital-analog hybrid architecture is one of Marvell's important innovations in LED drive technology. The so-called hybrid architecture has DSP cores in each chip 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 require the user to write, but there is a development tool where all the algorithms are solidified. With this OTP you can adjust the dimming curve of the driver chip. Another key point is that unlike using a microcontroller to run an algorithm, this does not require software development.

Take Marvell's single-stage LED driver IC 88EM8183 introduced last year as an example. It adopts Marvell's unique mixed-signal architecture and advanced dimming control technology. It has dozens of patented technologies in terms of algorithm and architecture; 88EM8183 can be programmed through OTP and Change the external resistor to adjust the dimming curve. Smooth dimming down to 1% LED current can be achieved smoothly, compared to similar LED driver solutions typically achieving only 10% to 20% dimming. With this range of dimming, the human eye does not feel much change in light intensity, so the 88EM8183 significantly improves performance. It is the industry's best solution for dimming and cost-effectiveness, with dimming efficiency of 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 and rear dimmers or digital dimmers. The compatibility of the dimmer can reach 90%, while the competitors do well near 70% to 80%, generally less than 60%.

In particular, the 88EM8183 is also able to provide a wide range of output power platforms and provides customers with dimming and non-dimming, high voltage and low voltage unified platforms. Commercial downlights based on 88EM8183 have also been introduced to the market.