Date: 13/03/2009

Devices to protect High brightness LED from ESD

California Micro Devices has unveiled LuxGuard family of protection devices for ultra high brightness LED (light emitting diode) lighting applications. The LuxGuard family of protection solutions includes both LED submounts and sidemounts (TVS Diodes) for ESD protection and to enhanced thermal management capabilities.

The market for high power, UHB LEDs has expanded beyond traditional market segments such as status and alphanumeric display markets into a wider range of lighting applications, including handset display and keypad illumination, automotive, signage, residential and commercial lighting. "Improvements in performance, efficiency, cost and reliability for UHB LEDs have been important contributing factors to their rapid penetration, accounting for over 15 percent of the total market in 2008, up from 10 percent in 2007,"said Jagdish Rebello, Ph.D. Principal Analyst for LED markets at iSuppli Corporation. "iSuppli forecasts the revenue for UHB LEDs to increase from $1.5 billion in 2009 to $3.9 billion in 2012 at a compound annual growth rate of 47 percent."

"High power LEDs are more ESD sensitive than their lower power counterparts, and require external ESD protection for enhanced reliability. Improved thermal management in a silicon based submount at a lower cost than more expensive ceramic submounts creates significant customer value," said Kyle Baker, vice president of marketing for California Micro Devices. "LuxGuard submounts and diodes address these exacting requirements for ESD performance and thermal management for UHB LEDs."
LuxGuard Design Options

LuxGuard sub mounts provide integrated ESD protection at levels exceeding 15kV HBM (Human Body Model). The submount also helps to cushion the LED from stress due to thermal expansion coefficient differences between the LED and the lead frame, while the option of an aluminum top coat provides improved reflectivity.

CMD also offers TVS diodes mounted next to the LED die within the LED fixture as side mounts. ESD ratings vary based on die size, and are typically between 8kV and 15kV HBM.

Since High bright LEDs are more prone to ESD failure, LED manufacturers are mandating that ESD protection and thermal management ratings become a key specification for their products.