Supertex introduced the AT9919, an LED lamp driver IC designed specifically for solid-state lighting applications in automobiles, such as headlights, tail lights, brake indicator lights, dome lights, and panel backlights. The chip is AEC-Q100 compliant and drives LEDs using a buck topology. It is available in a compact, eight-lead, DFN package. Thanks to its hysteretic control function, a constant output current to the LED string is maintained at all times, thereby improving the reliability and lifetime of the LEDs. LED brightness is achieved through a PWM control signal. The IC drives loads of up to 1 A at over 90% efficiency from input voltages ranging from 4,5 to 40 V.