LED array driver offers all-around protection

April 02, 2013 // By Christoph Hammerschmidt
Aiming at automotive interior and exterior lighting applications, Allegro MicroSystems designed the A6263 - a linear, programmable current regulator providing up to 100 mA from each of 4 outputs to drive arrays of high brightness LEDs.

current from each output, accurate to 5%, is set by a single reference resistor. Current matching in each string is better than 10% without the use of ballast resistors. Driving LEDs with constant current ensures safe operation with maximum possible light output.

The IC provides protection against the following common faults, including LED string shorted to GND, single or multiple LED short, LED string open, IC pin open/short, and over temperature. If one LED string is open or shorted to ground, the offending string is disabled, while other LED strings continue to work.

A temperature monitor is included to reduce the LED drive current if the chip temperature exceeds a thermal threshold. If necessary, this thermal derating threshold can be adjusted or disabled.

The device comes in an 8-pin SOIC (package LJ) with exposed pad for enhanced thermal dissipation. It is lead free, with 100% matte tin leadframe plating.

For further information visit http://www.allegromicro.com