The automotive LEDs of the CSL0901 (standard brightness) and CSL0902 (high luminosity) series guarantee high reliability in automotive instrument clusters in accordance with automotive standard AEC-Q102.
Rohm has increased the position of the light source in standard LEDs from 0.18 mm to 0.49 mm, which significantly reduces light losses to the environment. In addition, the size of the LEDs has been reduced by about 18 times compared to conventional reflector LEDs.
All LEDs are designed in such a way that the luminosity does not deteriorate even at high temperatures. To further improve reliability, Rohm has developed a new resin type for blue, green and white LEDs. In high-temperature tests with blue LEDs, the company succeeded in improving the residual brightness by approx. 80 % compared to conventional products. In addition, the high precision of the manufacturing process (e.g. die bonding, potting) allows a five to sevenfold increase in core brightness compared to conventional LEDs while retaining the compact 1608 size (1.6 mm x 0.8 mm).
In order to prevent light losses of LEDs into the environment, most automotive combination instruments are equipped with shields. However, light losses remain a challenge, as there is little space between the shielding and the printed circuit board to compensate for the expansion caused by the temperature change. Some LED applications, such as automotive and industrial systems, where electrical components are exposed to harsh conditions, require components with high reliability that can better withstand the aging effects of extreme environments.
To meet these requirements, Rohm developed the industry's first products for applications that require high component level reliability. These include, for example, the first silver-free high-brightness LEDs that are resistant to the effects of sulfur. Sulphur formation is one of the main causes of the aging process.
Further information: www.rohm.de