National Semiconductor Launches High-Brightness LED Driver to Simplify Zone Lighting Design
A highly integrated driver that evenly distributes current to multiple LED strings using a proprietary control method

June 7, 2011 – National Semiconductor Korea (CEO: Choi Chung-won) announced today the launch of the LM3466, a highly integrated linear LED driver that simplifies the design of high-power lighting fixtures, such as streetlights, where light is distributed over a wide area. Composed of only a few passive components, the LM3466 provides a complete system that enables each LED string to be driven from a conventional AC/DC constant current power supply.

Recently used LED drivers often require multiple components to accurately drive LED strings. Furthermore, the issue becomes more complex when designing to maintain even current distribution across the LED strings. National's LM3466 solves these problems by incorporating MOSFETs and utilizing National's proprietary control structure. Due to its high integration density, the LM3466 allows for driving LED strings using a basic design consisting of a single resistor and a single capacitor, even when using only a single unit. Additionally, complex systems can be constructed by repeating the strings in parallel.
The LM3466 adopts a unique dynamic current equalization control structure that enables communication between each LED driver, allowing current to be distributed evenly or proportionally among multiple active LED strings without requiring LED binning. Additionally, when string operation is not in progress, each LM3466 automatically distributes current evenly among the remaining strings to maintain a relatively constant output power.

National plans to demonstrate the LM3466 at the Guangzhou International Lighting Fair (Hall 8.1, Booth A43) held in Guangzhou, China from June 9 to 12.

Technical Features of the National LM3464 LED Driver
National's LM3466 linear LED driver features an integrated 70V, 1.5A N-channel MOSFET and has an input range of 6V to 70V. LED strings with a maximum stack voltage exceeding 70V can be driven with slight modifications to external components. The LM3466 offers technical features such as fault output, input under voltage lockout, current limiting, and thermal shutdown protection.