Direct-type LED backlight architecture TV large-scale development still takes time

Zhao Donghui, vice president of Fairchild's Korea Power Conversion Division, is improving the thermal performance, reducing EMI problems, and reducing the number of channels and LED strips. These are the main technical challenges facing LED system manufacturers. It is also a major problem to achieve the cost of lower 3D model design while maintaining visual quality, higher passive component requirements and trade-off balance. O 2 Micro is believed that the future development trend of LED drivers is mainly concentrated on multi-channel equalization and regional dimming. Multi-channel equalization means that when multiple strings of LEDs are connected in parallel, if a string of LEDs fails or is damaged, in order to keep other string LEDs still functioning properly, it is necessary to consider the application of current matching in multiple LED strings, including series and parallel LED strings. . The bumpy LED driver chip allows for 3.1 to 3.5V LEDs forward voltage range (Tolerance in forward voltage of LEDs), and its consistency and efficiency are higher than CCFL. Area dimming technology is used to dim the backlight portion of a specific area on the screen, or to illuminate different areas to make the picture look darker or brighter, while the edge-lit LED backlight technology can only be comprehensive. Brighten or dim. This dimming method is especially suitable for the design of high contrast TVs. Area dimming saves the number of light sources used and makes the picture area look more realistic. O 2 Micro can provide global dimming and local dimming control chips to support market demand. In the first half of the year, LED prices have stabilized. The backlight of LCD TVs is gradually being replaced by LEDs. According to the prediction of the Topology Industry Research Institute, the penetration rate of LEDs has risen rapidly in 2011. For example, LED displays have risen from 20% to 48%, and LED TVs have climbed from 20.4% to 50%, which has become the main driving force for LED applications. Such a large market size has also attracted many LED drivers and packaging manufacturers to join them. Currently active LED backlight driver manufacturers include: O 2 Micro, MPS, AnalogicTech, TI, Fairchild, Li Wei, etc. The main LED packaging factories are: Yiguang, Dehao Runda, Ruifeng, Foshan Guoxing and so on. The main markets for O 2 Micro are the LCD TV, LCD and notebook markets. The relevant person in charge of the company told the international electronic business reporter that in the third quarter and the fourth quarter of 2010, the above markets experienced some pressure on inventory adjustment; however, with the coming of Christmas and the Chinese New Year, the recent supply and demand in the market Already close to balance. With the increase in the ratio of LCD TVs with LEDs as backlights, the emergence of new TVs such as 3D TVs and smart TVs, and the demand for new NBs driven by the launch of Intel's new platform, O2 Micro considers the supply and demand of LED driver chips in the next six months. Maintain a balanced situation.

Ruifeng Optoelectronics TV Project Manager Yang Zhiyong Ruifeng Optoelectronics has 10 years of packaging process precipitation, and is also very concerned about the TV backlight market. The person in charge of the company disclosed to the international electronic business reporter that at present, domestic first-line brands such as Konka, Skyworth and Changhong are important customers, with monthly shipments of 10-15KK, and the delivery period has been relatively normal. It is reported that Ruifeng invested a large amount of funds in 2010 to purchase related equipment, and the production capacity has more room to play. Due to the establishment of strategic partnerships with many well-known raw material manufacturers including CREE , Jingyuan and Yiquan, Ruifeng Optoelectronic TV Project Manager Yang Zhiyong expects that the price of Ruifeng Optoelectronics' 5730 and 3020 products will stabilize in the first half of 2011. In addition, due to the significant addition of MOVCD equipment from the Korean, Taiwanese and mainland epitaxial manufacturers in 2009-2010, "I believe that in the next few years, LED chips as the main material will definitely reduce prices, while the demand for LED TVs Increase, as well as the development of the lighting market, when the overall demand for LEDs is greatly increased, the price of LEDs is bound to be lowered to be closer to the requirements of ordinary people." Yang Zhiyong said. Since TV brand manufacturers pay close attention to the reliability of LED chips, and LED TVs have only been launched in the market for about two years, there are still many problems that require time to verify. Yang Zhiyong said that Ruifeng Optoelectronics has always used Taiwanese chips and communicated with European and American chip manufacturers. As for why the local LED chip is not used, Yang Zhiyong said that local manufacturers need to continue their efforts in the following areas to meet the requirements of LED TV customers: 1) reliability; 2) productivity; 3) brightness; 4) patent issues.