In stand D31 at LuxLive (the UK's biggest lighting show) at ExCel London (19-20 November), Plessey of Plymouth, UK is presenting the results of its partnership with Litecool Ltd of Sheffield, UK (which manufactures heat management solutions for LED lighting products), showcasing its large-area LED die assembled in the Litecool MicroSpot product.
Litecool’s module allows the LED diodes to be mounted directly onto the heat spreader without anything underneath to obstruct the escaping heat. This is claimed to offer lighting product designers an LED module that stays cooler, allowing the use of smaller, lower-cost heat sinks and hence helping the LED to stay efficient, maintain good light quality and last longer.
Picture: Plessey’s large-area LED.
Plessey’s large-area LED die is based on its gallium nitride on silicon MaGIC (Manufactured on GaN-on-Si I/C) high-brightness LED technology. The large die benefits from three core features of the Plessey process: the low thermal resistance of silicon; a single-surface emitter die design; and 6-inch wafer processing. To exploit these benefits, Plessey has produced a 20mm2 die design (i.e. 4.5mm x 4.5mm) generating up to 5 Watt of blue light over a 400-480nm wavelength range.
Litecool has packaged Plessey’s large 4.5mm single-source LED emitter into its 10 Watt MicroSpot package with thermal resistance (junction to heat-sink) of just 0.7C/Watt, producing a beam angle of just 18 degrees and a luminance size of just 42mm.
“We have used our latest generation of technology to ensure groundbreaking thermal resistance for this unique package,” claims Litecool’s CEO James Reeves. “This powerful single-source emitter works exceptionally well with secondary optics and with our technology keeping it cool,” he adds, highlighting the spotlight market, where high lumen density is essential.
The heat management of LED die is a critical aspect of the design of lighting products adopting LEDs, notes Plessey’s marketing director David Owen. “The use of Litecool’s LED module technology enables us to maintain the lumen density not just at source but at luminaire level - a 10 Watt spotlight that is just 42mm in diameter.”
“Recent performance improvements in the efficacy of our LEDs have enabled Plessey’s GaN-on-silicon MaGIC LEDs to be competitive with any LED technology,” he adds. “Plessey’s technology has already shown how we can overcome what up to now has been a significant cost barrier in large-scale LED illumination.”
