Allegro MicroSystems, Inc. has released a new family of automotive-grade, high-current LED driver ICs with extensive diagnostics and protection features. The A6265, A6266 and A6267 are DC-DC converter controllers, with the A6265/A6267 configurable as either boost or buck-boost and the A6266 in boost only. All provide a programmable constant current output for driving high power LEDs in series, ensuring identical currents and uniform brightness. The devices are capable of driving up to 15 LEDs at currents of 1 A or higher based on the external logic-level MOSFET. These devices are targeted for automotive and industrial LED driver applications, in particular exterior front and rear automotive lighting.
The devices provide a robust, high performance, cost-effective solution using an external MOSFET and minimum additional external components. The maximum LED current is set with a single external sense resistor and can be modified using a current reference input. Direct PWM control is possible via the enable input, which also provides a shutdown mode. The dimming schemes for A6265 and A6267 differ slightly, offering flexibility to the designer with a choice of drop-in devices.
Integrated diagnostics and two fault outputs give indication of under voltage, chip over temperature, output open circuit, LED short circuit and LED under current and can be configured to provide short to supply and short to ground protection for the LED connections. The ability to detect one or more shorted LEDs is a unique feature of all the devices.
All three devices (A6265KLPTR-T, A6266KLPTR-T and A6267KLPTR-T) are available in a 16-pin eTSSOP package (suffix LP) with exposed thermal pad and are priced at $1.89 in quantities of 1,000.