Design Of Constant Current Power Supply For High Power IP65 LED Flood Driver

           

                  In today's global energy shortage environment, energy conservation has become a trend. At the same time, the country also vigorously advocated energy saving and emission reduction, the end of the 2008 Beijing Olympic Games and the upcoming 2010 Shanghai World Expo are invariably green energy-saving as the theme, which gives the development of LED lighting industry in China has brought great historical opportunities. High-power LED with light efficiency, low power consumption, long life, high stability, pure color, good security, strong controllability and other advantages, is gradually replacing the previous light source, began to be widely used in full-color display, traffic lights, car headlights, background light, landscape lighting, special work lighting, etc., become a new generation of lighting field of green light. According to the domestic authorities forecast, in the Olympic Games, the World Expo, driven by the strong, China LED lighting market scale from 2007 to 4.85 billion yuan rapid growth to 2010 of 9.81 billion yuan. Experts analysis that China LED lighting industry will usher in the new peak of development around 2010.IP65 LED Flood Driver

                  Generally speaking, high-power led power at least 1W above, currently more common there are 1W, 3W, 5W, 8W and 10W. Known as "green light source", it is moving towards large current (300ma~1.4A), high Efficiency (60~120LM/W), and adjustable brightness. However, the luminous intensity of the high-power LED is determined by the current flowing through the LED, excessive current will cause the attenuation of LED, the current too weak will affect the luminous intensity of LED, so the LED driver needs to provide constant current power supply to ensure that high-power led use of the security, but also to meet the expected brightness requirements, and to ensure the brightness of each led, chroma consistency. Therefore, traditionally used to drive light bulbs (tungsten), fluorescent lamps, energy-saving lamps, sodium lamps and other light source is not suitable for direct driving high-power led. It is necessary to solve the problem of step-down, isolation, PFC (power factor correction) and constant current by using mains power to drive high-power LEDs.IP65 LED Flood Driver

                 At present, the market has a thousands on the high power led constant-current driver-specific chip, there are Guang Peng (addtek), point Crystal (Siti), Crystal Chyi (SCT), China Resources Silicon Wei (PT), the United States has a supranational (SUPERTEX), Texas Instruments (TI), the United States, the country half, the United Kingdom Ceteko (Zetex) and other well-known manufacturers. Most special-purpose chip using hysteresis converter, low voltage input range, can be step-up, can step-down, PWM control, power switch can be built-in or external, output current can reach 1.5A, built-in over-voltage, undervoltage, open/short circuit and temperature protection circuit.IP65 LED Flood Driver