Allegro adds two LED drivers for automotive headlights

Allegro MicroSystems, Inc. has added two LED drivers to its automotive lighting portfolio with the introduction of the A80803 and A80804 controllers. Both products help designers reduce the number of ICs required to create safety-enhanced automotive lighting systems, said Allegro. The ICs can be used standalone or integrated into advanced driver assistance system (ADAS) applications.

The A80803 LED driver leverages multi-topology conversion and IP to enable smooth high/low/high beam transitions in a single IC, eliminating the need for a second LED driver. The A80804 linear LED driver provides high power for automotive lighting applications through multiple, independently-configurable channels, each with an independent enable/PWM input

(Source: Allegro MicroSystems)

A80803 LED driver

Addressing common pain points when adding advanced functionality to automotive headlights, the A80803 is a switch-mode, constant-current controller designed for high-power LED automotive lighting applications. The multi-topology, single-ended controller design, combined with wide input/output voltage capability, provides a universal solution for a variety of use cases and/or number of LEDs. Configuration options include SPI-based control or EEPROM-based end-of-line programming for standalone operation.

(Source: Allegro MicroSystems)

Other features include a “unique” slew-control feature that minimizes LED current overshoot and undershoot while transitioning between high and low beams, and diagnostics for ASIL capability, with two programmable fault pins and reporting via SPI.

A80804 LED driver

The A80804 is Allegro’s first four-channel linear driver for high-power LEDs. In addition to targeted applications such as DRL/position and stop/taillights, it enables features such as sequential turn signals, animation effects, and theater-style transitions. No switching elements or inductors are required, said Allegro, and the A80804’s low EMI output helps it achieve CISPR25 Class 5 compliance. It also offers multiple analog and PWM dimming methods, dual brightness mode operation, and is configurable without the need for a microcontroller.

(Source: Allegro MicroSystems)

Other key features include the ability to switch between low and full intensity for applications including stop/tail or DRL/position lighting, without the need of a local microcontroller, and selectable LED current slew-rate control for tuning PWM edge times for better EMI performance. A unique “MINOUT” function is said to significantly reduce power losses by dynamically adjusting for the inherent changes in LED Vf versus temperature.

The A80804 also can parallel multiple devices to extend the number of LED strings. It also provides a variety of protection capabilities to protect the device and the LEDs and an integrated/optional derating for high Vin and/or temperature.

Both LED drivers offer multiple method for analog LED setting/control, LED binning, NTC foldback or hybrid dimming. They also provide multiple methods for PWM LED control via an internal PWM signal (standalone mode) or an external PWM signal for direct PWM control on the EN/PWM pin (MCU mode).

The A80803 is available in a thermally-enhanced 32-pin, 5 × 5-mm QFN package with a wettable flank, and the A80804 is available in a 32-pin 5 × 5 mm QFN package with a wettable flank. Contact Allegro or authorized distributors for pricing and samples.