Allegro MicroSystems has developed a new device – the A6263 – that incorporates a linear programmable current regulator providing up to 100 mA from each of four outputs to drive arrays of high brightness LEDs. It is targeted at the automotive market for applications such as map and dome lighting as well as exterior accent lighting.
The device outputs can be connected in parallel or left unused as required. The regulated LED current from each output is set by a single reference resistor. Current is matched in each string without the use of ballast resistors. Driving LEDs with constant current ensures safe operation with maximum possible light output.
The A6263 incorporates protection against a range of common faults, including LED string shorted to ground, single or multiple LED shorts, LED string open, IC pin open or 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 de-rating threshold can be adjusted or disabled.
The Allegro A6263KLJTR-T is offered in an 8-pin SOICN package (suffix LJ) with exposed thermal pad for enhanced thermal dissipation.