Second, I represented, that is, the constant current control mode switching power supply drive. This is an ordinary switching power supply chip as the core conversion device, the chip a lot, such as the PI TNY series, TOP series, ST's VIPER12VIPER22 Fairchild's FSD200, and even with only MOS transistor or a tube of RCC, etc. can do. Advantage of low cost, reliability is good. Because the average price of switching power supply chip is not only good, but after extensive use are the classic products. In fact, as this IC is generally integrated MOS, MOS than the 9910 plus convenient, but control more complex, require the addition of constant current control device, you can use transistors or operational amplifier. Magnetic components can be inductive character of labor, can also be used with a gap of high-frequency transformer.I love transformers, because the inductor while the cost is very low, but I do not think its load capacity, a sense of the amount of addition is not flexible adjustment. So I think a better device selection, the common integrated MOS chip plus high-frequency switching power supply transformer, from the performance, cost, and are the best choice, do not go to any constant current IC with the kind of thing, not easy to use, and expensive.

2011 all kinds of LED lighting lamps market penetration of all increase, outdoor lighting of 5% or more, but the indoor lighting lamps and lanterns are still more than 1%. The whole, 2010 LED lighting lamps market share for 0.4%; In 2011 is expected to reach 1%.LED lighting applications market in China has started to form, predicts that as domestic LED lighting products subsidies support policies issued and implemented, the domestic LED lighting applications market will appear in the rapid growth in the past two years, see figure 4. With semiconductor lighting products performance of ascension and lower production costs, and at the same time, with the related application environment, such as standard, product certification and testing, engineering application design and demonstration, relevant policies and other industry environment improvement, LED lighting applications will be in 2011-2015 to keep higher growth rate. According to data calculation lamps, in 2015 is expected to in the lighting markets will be boosted by 30% or so, become the most competitive mainstream lighting one of light source.