STMicroelectronics Announces Highly Integrated, Design-Flexible Automotive LED Drivers

     ST's ALED6000 monolithic automotive-grade LED driver with integrated DC/DC converter is a low-BoM (bill-of-materials cost) flexible automotive lighting solution that guarantees consistent lighting intensity as the electrical conditions inside the vehicle fluctuate.

     The ALED6000 is suitable for driving vehicle exterior lighting systems, such as daytime running lights, headlights, tail lights, brake lights and turn signals as well as interior lighting, with a single string LED drive current up to 3A and a wide input voltage range from 4.5V to 61V.

     The ALED6000 implements digital dimming and provides a dedicated pin for PWM control signals, an enable pin, and a synchronization pin that ensures low noise for multi-device applications. The output current accuracy is less than 3.2%, and the output current is efficiently monitored through a current sense resistor with a typical voltage drop of 250mV. Quiescent current is extremely low, only 2.4mA in active mode and 11µA in shutdown mode. The ALED6000 also features a VBIAS auxiliary input pin and light-load pulse-skipping operation, ensuring energy-efficient operation over the entire load range.

     The on-chip power converter supports buck, buck/boost, and floating boost topologies, allowing the driver to flexibly power LED strings operating above or below the input voltage while handling supply voltage fluctuations. Additionally, if the input voltage drops near or below the preset output, the converter switches to a low dropout mode with a duty cycle close to 100%.

     If an overcurrent condition occurs, the ALED6000 will activate a pulse-by-pulse protection mode to limit the output current to the maximum preset value, in addition to a programmable soft-start circuit for inrush current limiting and thermal protection with automatic recovery. The output current limit and converter switching frequency can be set using external components, together with a low ESR capacitor, the performance of the inductor can be optimized for high energy efficiency, fast dynamic response, small size and low output ripple.

     AEC-Q100 qualified ALED6000 automotive LED drivers are now in mass production in HTSSOP16 package. Designers can use the STEVAL-ILL089V1 evaluation kit to speed up project development.