Automotive-compliant fast dimming linear LED controller

With an operating voltage range of 4.5 to 60V, the AL5816Q supplies an output drive current of 15mA to control LED lights through an external BJT, delivering a constant current of a few mA up to 1.5A, or higher LED current if a MOSFET is used. This ability to optimise the external transistor makes the AL5816Q well-suited for many automotive LED lighting applications, such as rear light clusters, interior illumination, instrument panels, and license plate lighting.

The combination of a high-input voltage and high-output drive current, coupled with a versatile high-voltage PWM dimming feature, means automotive manufacturers can realise a significantly lower BOM for a wide range of automotive applications using the AL5816Q. The five-pin SOT25 package requires very few external components and does not need a separate switching inductor. It features a high-voltage PWM input for LED light dimming.

The feedback pin operates at just 200mV, enabling the AL5816Q to control the LED drive current precisely while minimising the drop-out voltage and reducing the LED system power dissipation, particularly when compared against traditional linear LED controllers.

The high-output drive current allows the AL5816Q to drive a single LED, an LED chain or multiple LED channels, as required by automotive manufacturers. The PWM dimming input accepts a signal operating at up to 50kHz. The device also features a number of protection features including input undervoltage lock-out and overtemperature shutdown.

The AL5816Q is available in the SOT25 package and priced at $0.18 each in 1,000 piece quantities.