According to Darnell Group, the latest release of AC / DC power supply, the worldwide embedded AC / DC power supply market will grow from $ 11.8 billion in 2006 to grow to $ 14.8 billion in 2011, an annual growth rate of 5.8%. However, 500W AC growth rate above embed / DC power supply is twice the overall market, although its price fell fastest. This trend to higher wattage by the rapid growth driven applications, including blade servers, Ethernet power and data storage. Blade server power supply problems of concern, because they require power supply. A typical device in a blade server chassis built with 10 to 14 blade servers. Enclosures usually have up to four hot-swappable and redundant n + n 2kW power supply. Therefore, full-power blade server chassis can easily exceed 20kW. Higher power levels movements across a variety of applications, accompanied by a distributed power architecture, especially intermediate bus architecture, which increases the demand for rack-mount AC / DC front end. This corresponds with the demand, there has been a lot of new front-end power on the market recently. In addition to the increasing use of high-power front-end power other than the power supply has also been shown to promote these AC / DC power supply market development in a number of other trends: more attention to power efficiency; digital power steering. Due to the sharp rise in energy prices and the growing concern about greenhouse gas emissions is expected to typical efficiency AC / DC power supply will be improved in the coming years. In the power electronics industry, the embedded AC / DC power supply market is usually the most stable markets. But now there are a lot of applications, technology, business and management trends are generating the combined effect of this large and stable market, as well as its opportunities and threats. One of the most popular trends is the power wattage is growing, and more emphasis on power efficiency.