London, March 12 IANS | 5 months ago

We all know that LED lights are durable and save energy. Now researchers have found a novel way to make LED lamps even more compact while supplying more light than commercially available models.


And the key to success lies in transistors made of the semiconductor material gallium nitride.

LEDs are extremely sensitive to variations and spikes in power. To function properly, they need a driver that ensures a constant supply of power at all times.

"This driver, which takes the alternating current from the grid and converts it into direct current with a reduced voltage, has a profound influence on the light yield and lifetime of the LED lamp as a whole," said Michael Kunzer, group manager at the Fraunhofer Institute for Applied Solid State Physics IAF in Germany.

This prompted researchers to focus their attention on voltage transformers featuring gallium nitride (GaN) transistors.

During practical testing, the scientists found that the drivers developed using this new semiconductor material were extremely robust.

Components made of GaN can operate at higher currents, voltages and temperatures than standard silicon transistors.

"Heat plays a role both in the brightness and the service life of LED lamps," Kunzer added.

With the new semiconductor, the researchers were able to boost the efficiency of the GaN driver to 86 percent - between one and four percentage points better than its silicon equivalent.

"Nearly 20 percent of energy consumption worldwide can be attributed to lighting so it is an area where savings are particularly worthwhile. One should not underestimate the role played by the efficiency of LED drivers as this is key to saving energy," Kunzer noted.

(Posted on 12-03-2014)