Osram MultiLEDs Bring Color to Automotive Applications04-09-2013
Osram says that at 370 miilicandela (mcd) the blue is much brighter than in other multi-chip LEDs on the market. The specific sensitivity of the human eye reportedly makes the blue appear darker than it actual is. Therefore the high brightness of the blue is a big advantage. "The new LED can offset this darker perception so that the brightness requirements of the applications can be met for all color ranges," said Stephan Pawlik, LED Automotive Marketing at Osram Opto Semiconductors. "Whats more, a short-wave blue color has a pleasant saturated appearance. We have now succeeded to implement this color range in an RGB LED version."
The three LED chips are are independently controllable and are available in different brightness groups thanks to finely defined grouping (known as binning). They can be individually combined to produce a large color spectrum. The blue and green leverage the companys UX:3 technology, and the red uses its latest thin-film technology. The light is therefore extracted from the chip with high efficiency, resulting in what the company says is high luminous intensity. In the upper blue wavelength range, for example, a figure of up to 560 millicandelas is achieved at an operating current of 20 mA. Luminous intensity in candela (cd) corresponds to luminous flux in lumen (lm) emitted by a light source in a particular solid angle.
The typical thermal resistance between the chip and the solder point is 127 K/W for blue and green, and 96 K/W for red. Osram says that the MultiLED was developed specifically for applications in the automotive sector and has been equipped with appropriate properties. It has been designed for long availability, has improved corrosion resistance and integrated ESD protective diodes (2 kilovolts). It therefore meets all the requirements of an automotive certified component. The standard SMT package measures 3.3 x 3.0 x 1.8 mm and has the same footprint as the predecessor version.