LIN RGB LED controller drives up to eight RGB channels

Melexis has introduced the MLX81118 multi-channel, LIN RGB LED controller with 24 LED driver outputs, enhancing and simplifying the design of animated interior and exterior automotive lighting. In addition, the MLX81118 reduces the bill of materials with the capability to drive eight RGB channels, and it features a new dual input-voltage capability that significantly lowers LED power dissipation for LIN applications.

Expanding its LIN RGB LED controller family, the MLX81118 adds new features that increase reliability, ease thermal management, and maximize temperature stability, said Michael Bender, LIN product line manager at Melexis.

Click for a larger image. (Source: Melexis)

Designed for ambient lighting and animated lighting applications in a LIN system, each of the 24 outputs of the MLX81118 is capable of sourcing up to 60 mA. The independent PWM control, configurable up to 16-bit resolution, allows the controller to achieve any color point and brightness level.

In addition, the RGB LED controller features built-in direct and indirect temperature monitoring that enables temperature compensation for all channels, which is said to ensure stable color points over the full temperature operating range from -40 °C to 125°C.

The MLX81118 can operate from a supply voltage as low as 4 V for consistent performance as the vehicle supply voltage fluctuates, such as during stop-start operation, said Melexis. It also includes built-in protection features such as 28-V jump start and battery overvoltage and undervoltage detection.

A key benefit of the MLX81118 is that it lowers LED power dissipation thanks to its new dual input-voltage capability that optimizes the driving voltage for the connected LEDs. This helps to simplify thermal management, enhance module reliability, and reduce power consumption, said Melexis.

The MLX81118 complements the MLX81115 and MLX81113 controllers to address different applications. Unlike the MLX81113, which is mainly used for classical ambient lighting functions, the MLX81118 is suitable for various applications where multiple RGB LEDs need to be controlled via one LIN node within one or several modules. An example cited is in door trim parts or dashboard applications.

The MLX81118 contains a complete LIN system, including the transceiver and protocol handler for connecting LED modules to the vehicle’s existing LIN network. The LIN interface is compliant with LIN2.x and SAE J2602 standards as well as ISO 18987. It supports auto-addressing according to the bus-shunt method. The LED controller is also compliant with ISO 26262 requirements, allowing use in functional-safety classified systems.

(Source: Melexis)

The LED control is handled by Melexis’ MLX16 FX 16-bit RISC microcontroller and the on-chip memory subsystem that includes 2 KB of RAM and 32 KB of Flash memory for the application and LED calibration coefficients as well as an EEPROM for additional customer data, said Melexis.

Click for a larger image. (Source: Melexis)

The MLX81118, housed in a leadless QFN32 5 × 5-mm thermally enhanced package, is in qualification now. It can be supplied with PPAP in accordance with AECQ-100. Resources include an evaluation board, in-circuit-emulator, and C-Compiler package, along with software, including a LIN driver, color mixing, math library, and IC initialization routines.

Earlier this year, Melexis introduced the MLX81117 multi-channel RGB-LED driver with better color-mixing accuracy for animated automotive lighting for enhanced safety features.