LEDs that are lighting up the market

Steve Bush looks at some of the LED product highlights at the euroLED 2011 exhibition which took place earlier this month in Coventry.

Sharp Europe showed its Mega Zeni 15W and 25W LEDs for the first time at this month's euroLED exhibition in Coventry. 

Announced in February, the 24x20x1.8mm multi-die devices radiate with efficiency up to 102 lm/W, flux up to 2550 lm, and CRI around 83. 15W Mega Zenis have a forward voltage of 37V and work at 400mA.

Inside, there are 96 LEDs arranged in a round pattern with eight parallel strings of 12. Luminous flux is 1,350-1,520 lm (4,000K 102 lm/W). 25W Mega Zenis also have a forward voltage of 37V, but this time operate at 700mA.

Their round LED matrix consists of 168 LEDs in 14 strings of 12. Luminous flux is 2,300-2,550 lm (4,000K 98 lm/W).

The LEDs in both devices are cross-connected at every LED to allow the rest of each string to work if one die fails, and they are both use ceramic substrates.

“The serial and parallel array of the LED matrix ensures fail-proof operation,” said Sharp. “The flat surface of the ceramic plate and the soldering points already in place make it possible to attach the modules to a suitable heat sink without too much effort or additional connecting material.”

Operating life is claimed to be 40,000 hours at 80°C.

Carclo Technical Plastics has taken its injection moulded 10mm collimating optic and transformed into a linear extruded optic, revealing it for the first time at ­euroLED.

Called the Continuous Strip Optic, it is 11mm across, 4.7mm high, and designed to manage the light from a line of small surface mount LEDs like Luxeon Rebel, Cree XP, Osram Oslon, Nichia 119 and Seoul Z5.

“In addition, it also works with the increasingly popular 0.5 and 0.25W linear LEDs such as the Cree ML-E and ML-B, as well as the Nichia 157 and 123,” said the firm.
Carclo is aiming to replace individual optics in linear LED arrays under cabinets and in shops, museums and aircraft interiors, as well as for architectural wall washing, cove illuminating and corridor lighting.

“As it longitudinally diffuses the LED light sources, this strip optic can be used for both white light applications as well as RGB mixing,” said the firm. 
 
Made in Wakefield and unveiled at EuroLED, Harvard Engineering has extended its CoolLED range of mains LED power supplies.

There is now a 40W 1A driver for strings of 24-40V that includes a 5V auxiliary output for fan cooling.

“The auxiliary 5V 2W output is suitable for powering fans: Nuventix’ Synjet for example,” said the firm.

There are two types: a 96x46x29mm open frame type for mounting inside light fittings and a 144x47x32mm Class 2 insulated version for remote mounting. Power factor is 0.98 and maximum efficiency is 88%.

Alongside these is a mains phase-cut-dimmable 700mA driver delivering up to 33W for 27-47V strings, with a 22W option for 16-32V strings. Dimming is <5% (depending on dimmer) to 100%

Lastly new from Harvard is a 30W DALI-dimmable driver range with six versions between 350mA and 1.4A. Dimming is 10-100%, plus ‘off’. 

Molex has introduced a solder-less holder for Bridgelux ES lighting LEDs.

ES series LEDs produce 400-2,000 lm in three colour temperatures and are aimed at applications suited to: 20-100W incandescent and halogen bulbs, 7-42W compact fluorescents, and 18-50W HID sources.

They come on bolt-down ‘star’ and square substrates with solder pads on top and, for lighting OEM use, Molex’s holder extends the bolt-down theme.

The holder includes sprung contacts which engage with the LED solder pads as it is mounted over the LED.

These contacts are electrically connected to clip-type wire-trap terminations, allowing stripped wires to be pushed home into the holder rather than soldered.

“By using Molex’s interconnect knowledge, our holders provide Bridgelux ES Array customers with a single piece, solder-less connection that is easy to install,” said Jeremy Zidek, product manager at Molex.

Avago Technologies has announced a 120° surface mount LED for backlighting adverts, vending machines, electrical appliances and gaming machines.

The 3.9x2.8x1.9mm ASMT-UWB1 comes in a silicone-encapsulated plastic leaded chip carrier package and typically offers 2.8 lm at 20mA and 3.1V. 

There are bins between 4,500 and 8,000K.