Smallest reflector-type, high brightness 3-colour LED for matrix displays

February 01, 2017 // By Graham Prophet
Rohm Semiconductor has an ultra-compact reflector-type LED optimized for consumer devices such as matrix light sources for gaming and wearables that demand increased miniaturization. Its small footprint and high ESD resistance design provides design flexibility in matrix applications.

The MSL0402RGBU reflector-type 3-colour LED is believed to be packaged as the smallest size in the industry (1.8 x 1.6 mm). This enables high-density mounting and provides excellent colour mixing characteristics, ensuring support for high resolution LED matrices.

 

In order to turn on matrix light sources it is necessary to take measures against ESD. Unlike conventional solutions that utilize a Zener diode, the MSL0402RGBU adopts an element with high ESD resistance. This eliminates the Zener diode and at the same time prevents light emission of unwanted blocks in matrix circuits, resulting in clearer display.

Until now, 3.5 x 2.8mm LEDs have typically been used in dot matrices, resulting in a coarse display which can be problematic when higher resolution is demanded. These new devices reduce mounting area by 70% over Rohm’s conventional LEDs. This makes it possible to construct high brightness, ultra-high resolution matrix light sources that contribute to improved performance and display capability in gaming and other applications.

 

Anti-sulphuration performance increases reliability; the combination of silver plated frames and silicon resins used in conventional LEDs will typically result in a drop in brightness after 1 year due to 30% sulphuration caused by sulphur components in the air originating from tobacco smoke and exhaust gases, presenting problems for long-term reliability. The MSL0402RGBU uses a gold plated substrate that prevents sulphuration even when silicon resin packages are used. This minimizes brightness degradations and contributes to greater long-term application reliability.

 

Normally, Zener diodes are used as a countermeasure to static electricity in LEDs. However, in matrix circuits this can cause current to flow to other LEDs, resulting in unwanted light emission. In contrast, the MSL0402RGBU employs a high ESD resistance element that eliminates the need for a Zener protection diode, ensuring superior display performance in matrix circuits.

 

 







Part No.

Color

IF (mA)

VF (V)

Brightness (mcd)

λD (nm)

 

MSL0402RGB

(6pin)

R

20

2.1

400

624

G