ALED6000 Single Channel Automotive LED Driver with Integrated DC/DC Converter and Dimming Capability

STMicroelectronics has revealed a single-chip automotive LED driver ALED6000 with integrated DC/DC converter that allows design flexibility and keeps the lighting intensity consistent as electrical conditions within the vehicle fluctuate. The ALED6000 drives a single string of LEDs at up to 3A and has a wide input-voltage range of 4.5V to 61V. It is suitable for exterior lighting such as daytime running lights, headlights, rear lights, stop lights, turn signals, and interior lighting. The ALED6000 implements digital dimming and has a dedicated pin to apply the PWM control signal. Moreover, there is an Enable pin and a Sync pin that ensures low noise in multi-device applications.

The ALED6000 LED Driver ensures high efficiency across the load range as it features a VBIAS auxiliary-input pin and pulse-skipping operation at light load. The output current is accurate within 3.2% and is monitored efficiently with a sense resistor that has a typical voltage drop of 250mV. The quiescent current is extremely low, at just 2.4mA in operation and 11µA in shutdown. The on-chip 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. In addition, the converter can operate in low-dropout mode with close-to 100% duty cycle if the input voltage falls near or below the programmed output.

In the event of over-current, the ALED6000 invokes pulse-by-pulse protection to limit the output current at the preset maximum. There is also programmable soft-start circuitry to limit inrush current, and thermal protection with auto-recovery. Both the output-current limit and converter switching frequency can be selected using external components, allowing the inductor to be optimized for high energy efficiency, fast dynamic response, small size, and low output ripple in conjunction with a low-ESR capacitor.

Features of ALED6000 LED Driver

• AECQ100 qualification

• Up to 3A DC output current

• 4.5V to 61V operating input voltage

• RDS(on) = 250 mΩ typ.

• Adjustable fSW (250 kHz - 1.5 MHz)

• Dimming function with dedicated pin

• Low IQ shutdown (10 µA typ. from VIN)

• Low IQ operating (2.4 mA typ.)

• 3.2% output current accuracy

• Synchronization

• Enable with dedicated pin

• Adjustable soft-start time

• Adjustable current limitation

• Low-dropout operation (12 μs max.)

• VBIAS improves efficiency at light load

• Auto recovery thermal shutdown

Applications of ALED6000 LED Driver

• Suitable for automotive systems

• HB LED driving applications

• Halogen bulb replacement

Prices and Availability of ALED6000 LED Driver

The ALED6000 automotive LED driver is in production now in the HTSSOP16 package, priced from $2.25 for orders of 1000 pieces.