4-Channel High-Power Linear LED Driver With Individual PWM Control

The A80804/A80804-1 are linear, programmable current controllers that make it possible to regulate LED current in four strings using external MOSFETs. The linear LED drivers provide high power for automotive lighting applications through multiple, independently-configurable channels. In addition to targeted applications such as DRL/position and stop/tail lights, the A80804/A80804-1 give lighting designers increased design flexibility for popular features such as sequential turn signals, animation effects, and theater-style transitions.

The A80804/A80804-1 are Allegro’s first four-channel linear drivers for high-power LEDs, and help lower total system costs by reducing the number of ICs required to meet customer needs. No switching elements or inductors are required, and the low EMI output helps both ICs achieve CISPR25 Class 5 compliance. They also offer multiple analog and PWM dimming methods, dual brightness mode operation, and are configurable without the need for a microcontroller.

The A80804/A80804-1 incorporate “MINOUT” function to feed a signal back to a pre-regulated supply, which helps designers significantly reduce power losses by dynamically adjusting for the inherent changes in LED Vf versus temperature. They achieve <1% PWM duty cycle at 200Hz, with adjustable on-to-off slew rate control, helping provide a wider dimming range for transitions and lighting effects.