Display industry has the smallest two-color LEDs

The new two-color chip LEDs from Rohm Semiconductor claim to be the smallest in the display industry. The Japanese component supplier also asserts that its SML-D22MUW LEDs enhance the reliability of high-resolution displays with a backside electrode configuration.
Conventional numerical displays utilize a single color to indicate numbers in industrial equipment and consumer devices. And while there is a growing need to change the color for making it easier to recognize abnormalities, it typically entails utilizing two separate LEDs. That, in turn, doubles the mounting area, increases board size, and adds to development costs. Not surprisingly, therefore, chip LEDs are being increasingly used for numerical displays.

The SML-D22MUW integrates two chips in the same package size as conventional single-color LEDs, making it possible to emit multiple colors in a smaller footprint. It enables thinner displays by reducing the board space by 35% over standard 1.5 x 1.3-mm two-color LEDs.

Besides element miniaturization, Rohm’s new LED solution leverages the company’s PICOLED mounting and wire-bonding technologies to mount two chips — red and green — in a compact 1.6 x 0.8-mm package. And it’s of the same size as conventional single-color LEDs.

Moreover, a close configuration of color elements results in rich color-mixing properties, which make it possible to produce not only red and green colors but a number of intermediate colors as well. Next, a backside electrode configuration allows mounting in narrow spaces, which facilitates a high-definition display for dot-matrix and other applications.

Finally, the two-color chip LEDs take into consideration the usage conditions during reflow and adopt countermeasures to prevent solder penetration within the resin package. And that eliminates failures due to short-circuits and ensures greater reliability.