ST Microelectronics presents a design solution how to drive an array of High Brightness LEDs and detect wrong LEDs on the display, using STP08CDC596 family with constant current output per channel. Two reference boards based on this driver solution will be available soon. The first one is STEVAL-ILL002V1 with OSRAM LEDs and the second one is STEVAL-ILL002V2 with TOSHIBA LEDs. In order to demonstrate the LEDs Array in office environment any laptop power adapter can be used.

The principle of this reference board is shown in the left figure. The microcontroller (8-bit μC ST7FLITE39) sends the DATA through SPI (serial peripheral interface) to all the LEDs drivers and provides blinking speed and brightness regulation. The output stages of the drivers are implemented as current sources.  This is an advantage of these drivers, because constant current (brightness and light colour) is set for all LEDs and so there is no brightness and colour differences between LEDs also in big monochrome displays. Another big benefit of STP08CDC596 LEDs driver is that the error detection feature allows detection of faulty LEDs on the display. The error detection mode can be entered through a SW routine and so this LEDs driver could be made pin to pin compatible with STP08xx596 LED driver family.