Thanks to recent government legislation and incentives in the area of general illumination in Asia, Europe and the Americas, LEDs are becoming more widely used in street lamps as well as other outdoor lighting applications. This is because they provide superior reliability, efficiency, dimming, and robustness when compared with traditional CFL and high or low pressure sodium lamps. Moreover, they do not contain the hazardous mercury or halogen gases found in traditional fluorescent and HID technologies. TI’s LM340x family of buck, boost, and buck-boost LED drivers support a wide input voltage range and are fully optimized to support the demands of outdoor and street lamp LEDs. The buck regulators provide up to 96% efficiency, thereby increasing the robustness and reliability of the whole system, while the boost regulators are designed to support a large number of LEDs in one string, reducing the cost of the total solution. The constant on-time architecture of these drivers further means that no loop compensation is required, reducing the number of external components needed. This means less design time and reduced system complexity for the users’ design.