STMicroelectronics introduces its automotive LED driver chip with integrated flexible DC-DC converter.
LED driver circuits drive an LED or LED strip with high efficiency and aim to extend the life of the driving lighting systems. Automotive LED drivers are designed such that it has a flexible architecture and suppresses the EMI caused due to vehicle fluctuations. The automotive LED drivers, in addition to driving LEDs with high efficiency, also work to keep the light intensity constant despite the electrical fluctuations in the vehicle.
STMicroelectronics announces its ALED600 automotive LED driver chip consisting of an integrated DC-DC converter. The driver chip requires only a few external components, reducing the bill of materials. It is suitable for exterior lighting such as daytime running lights, headlights, rear lights, stop lights, and turn signals, as well as interior lighting.
The LED driver is designed to source up to 3A DC current for high power LED driving, and has a wide input-voltage range of 4.5V to 61V. The output current is accurate within 3.2% and is monitored with a sense resistor that has a typical voltage drop of 250mV. The quiescent current consumption is just 11uA when not running and 2.4mA during operation.
The integrated converter allows buck, buck/boost, and floating-boost topologies, giving flexibility to power LED strings that require a voltage above or below the input voltage while also handling supply fluctuations. The driver, moreover, implements digital dimming and has a dedicated pin for PWM signals. During over-current, the driver activates pulse-by-pulse protection to limit the output current at the preset maximum. There is also a programmable soft-start circuit and a thermal protection circuit with auto-recovery.
The maximum output current and the switching frequency can be controlled via external components. This allows designers to optimize circuits for high efficiency.
For further information please go to www.st.com/buck-current-regulators.