LED manufacturers continue to enhance their LED designs for automotive lighting, enabling greater differentiation in the car’s exterior and interior illumination as well as improving safety features. Many of the latest developments focus on several key areas: smaller form factors for space-constrained and sleeker designs, improved thermal performance, and flexible color control.
LED driver developments go hand in hand with these advances to support these next-generation LEDs, focusing on advancements in packaging, heat dissipation, and simpler designs for easier integration and space savings.
Here is a selection of LED and LED drivers introduced over the past year, targeting automotive exterior and interior lighting applications. They focus on a range of improvements that deliver smaller form factors, greater heat dissipation, higher system efficiency, enhanced light output, and precise color control.
A new generation of LEDs
Some of the latest automotive LED designs address the demand for sleek front lighting. One example is ams Osram’s OSLON Compact RM for next-generation slim headlamp systems. It addresses design aesthetics in automotive lighting with its high luminance, compact form factor, homogeneous light, and color appearance, allowing for the creation of signature lighting elements for brand identity, the company said.
The Compact LED is a 0.5-mm2 rectangular high-current chip, housed in a compact ceramic package. The small size enables optical systems with heights as low as 10 mm, enabling ultra-slim headlamp designs that were previously difficult to achieve, according to ams Osram. The two-pad package design supports solder stability on aluminum boards, suiting it for a variety of automotive lighting applications.
The LED delivers improved optical efficacy through its adapted light-emitting area (LEA) of 0.6 × 0.9 mm with an aspect ratio of 1:1.5. It features high luminance and uniform light output, free from dark zones, while maintaining high energy efficiency, a key factor for EVs.
The OSLON Compact RM for advanced front-lighting applications targets three light functions: low beam, static high beam, and adaptive driving beam (ADB) LED matrix systems. Thanks to its rectangular LEA, vertically oriented within the package, the OSLON Compact RM enables precise pixel-to-pixel alignment and provides a greater vertical light spread in ADB systems. At a driving current of 1 A, it claims an impressive luminance of 209 Mnits, which ensures maximum optical performance even with small lens components, according to the company.
Ams Osram also enhanced its offerings for automotive interior applications with the launch of its OSIRE E3030 RGB LED with significantly enhanced light output. Aimed at next-generation ambient lighting solutions, the RGB LED pairs a high light output in the 0.5-W range with precisely controllable color variety, meeting both function and aesthetic requirements.
Depending on the selected color location, the OSIRE E3030 delivers typical luminous emissions for red and blue, ranging from 22.4 to 40 lumens or from 7.1 to 14 lumens at a binning current of 200 mA, and from 28 to 50 lumens for green at a binning current of 150 mA. It offers a wide range of available wavelengths for an expanded color gamut and individually addressable color channels for greater flexibility in terms of color selection and color mixing.
The OSIRE E3030 measures 3 × 3 × 0.6 mm, suiting it for applications with space constraints. In addition, the delta arrangement of the LED chips ensures exceptional color-over-angle performance, according to the company.
The OSIRE E3030 is also resistant to vibration and temperature fluctuations, meeting automotive standards. It is AEC-Q102-qualified.
Also claiming ultra-small footprints and profiles, Lumileds has introduced two LED series—the LUXEON Versat 2016 and the LUXEON Altilon SMD-A—targeting a variety of automotive lighting applications.
The LUXEON Versat 2016 automotive LED is an AEC-Q-qualified LED portfolio with a broad color and performance range, measuring 2.0 × 1.6 mm with a z-height of only 0.52 mm. The LED not only offers standard direct and phosphor-converted colors but also LED-emission spectral tuning to match transmission characteristics of foils as used in car-body and grille illumination for superior color control, Lumileds said.
Targeting animated, personalized car-body lighting, the LUXEON Versat 2016 delivers features such as singular optical elements, backlit optical surfaces, and 3D illuminated structures for car illumination beyond traditional signaling into styling and communication lighting, the company said. The automotive LED can also be used in daytime running lights (DRLs), turn, stop, tail, and side-marker applications.
Lumileds also introduced the LUXEON Altilon SMD-A LED, claimed as the thinnest single-chip addressable LED, targeting high-performance automotive forward lighting. It has a z-height of only 433 µm, which allows for optical structures to be designed with greater accuracy and efficacy. This means the optics can be designed closer to the LED, which improves optical efficiency.
The advanced package is said to increase luminance, thermal capabilities, and robustness for demanding front fog, low/high beam, and ADB.
In addition, the small edges of the LUXEON Altilon SMD-A improve contrast, measuring 1:247, and produce a sharp, natural cutoff. Lumileds said reducing the gap between LEAs to 70 µm and achieving the optimal die-to-phosphor size increases luminance for further cost-performance improvements. The series is available in four configurations: 1×2, 1×3, 1×4, and 1×5.
For aftermarket automotive lighting applications, Cree LED, a Penguin Solutions brand, introduced the XLamp XE-B LEDs in an ultra-compact package for directional lighting applications. This latest XLamp Element LED extends the family into a smaller form factor, measuring 0.9 × 1.4 mm, while delivering high intensity in optical systems, whether used individually or in arrays, according to the company.
Claiming new levels of performance from an extremely small light source, the automotive LED delivers up to 60% higher intensity than existing LEDs with a larger, 1 × 1-mm light-emitting surface. While it is optimized for directional lighting applications that benefit from multi-color LED designs and suited for indoor directional lighting, architectural lighting, and entertainment lighting, it also targets aftermarket automotive lighting, in which compact size, high intensity, and precise color control are all key requirements.
The XE-B LED series is built on Cree’s advanced Element platform, enabling the smallest possible distance between the LED chip and the package edge, which allows tighter spacing, improved optical control, and seamless integration with secondary optics. It also features a large, electrically isolated thermal pad that supports advanced printed-circuit-board (PCB) designs, delivering a direct thermal path to the heat sink for excellent heat dissipation and long operating lifetimes, even at maximum current, the company said.
The XE-B LEDs enable precise and consistent color mixing with a consistent 1-A maximum current across all colors and a uniform package design. It offers 17 colors plus a full range of white options.
LED drivers optimize automotive lighting
Targeting improved safety, aesthetics, and personalization, Diodes Inc. offers the automotive-compliant AL5958Q matrix LED driver with a 48-channel constant-current source, capable of up to 32 scans. Suited for automotive dynamic lighting, the device targets narrow-pixel mini- and micro-LED displays, which require multiple RGB LEDs to produce animated, dynamic lighting with data and information. Applications include central information displays, cluster displays, head-up displays, grill and emblem lights, body LED panels, interior lights, and rear lights.
The AL5958Q features built-in intelligent matrix display command functions that reduce the processing overhead on the local microcontroller (MCU). Key functions include automatic black-frame insertion to mitigate blurs caused by scanning switches, reduction of last-scan- and next-scan-line ghost images to eliminate ghosting from parasitic capacitors, and suppression of short-LED caterpillars.
Other features include open-LED fail lines and staggered current output delay to minimize inrush current, as well as grayscale enhancement (also known as low-brightness uniformity compensation), a grayscale clock watchdog timer, and sleep mode for power savings.
Differentiated features include the integrated 16 N-MOSFETs, allowing support of both static and dynamic systems, and multiplex-pulse-density modulation technology that enhances the refresh rate of dynamic scanning systems without increasing the frequency of the grayscale clock. This mitigates electromagnetic interference (EMI) due to high clock frequencies, Diodes said.
The AL5958Q also features high, 16-bit resolution dimming, coupled with its RGB support, for highly precise brightness control and color mixing. The current output for each color group can be configured either through three external current-sensing resistors or by programming three 6-bit global current control registers.
The device also offers advanced diagnostic features and protection mechanisms for monitoring capabilities. These include error flag registers applied to LED open/short to read out each channel using open/short detection, undervoltage lockout (UVLO) protection, and a watchdog timer.
The AL5958Q is supplied in a wettable W-QFN9090-76/SWP (Type A1) package and operates in a –40°C to 125°C ambient temperature range. Multiple AL5958Q devices can be daisy-chained without limitation. Diodes also offers a standard compliance version, the AL5958, for industrial and commercial applications.
Lumissil Microsystems recently introduced the IS32FL3776 matrix LED driver for software-defined exterior lighting module applications. Enabling a combination of expressive and thermally efficient exterior lighting, these systems use matrix LED patterns to communicate vehicle intent, safety status, and driver-assistance cues, as well as brand identity.
The IS32FL3776, housed in a QFN-60 package, supports compact, individually addressable LED designs used in RGB mini-LED displays, full-width front-light strips, grille lamps, automated-driving-system marker lamps, and other vehicle lighting functions.
The IS32FL3776 integrates 36 constant-current sink channels and six scanning supply-switch controls to support a 36 × 6 matrix of up to 216 individually addressable LEDs. The dense matrix architecture targets large, intelligent signal display (ISD) lighting surfaces with fewer external components.
For high-quality animations, the IS32FL3776 features high-resolution, high-frequency, dithered pulse-width-modulation (PWM) control for fine brightness adjustment and a reduction in visible flicker and camera banding. Other features that help maintain uniform, artifact-free illumination across dense LED arrays include integrated current adjustment, matrix de-ghosting, low-headroom operation, and synchronized scanning.
This LED driver offers high-speed SPI and LumiBus UART interfaces that allow multiple driver ICs or distributed lamp PCBs to operate in synchronization for large-area displays and coordinated lighting animations.
The IS32FL3776 packs features for improved system efficiency and thermal performance. DCFB adaptive control is used to optimize the LED supply rail while maintaining only the headroom needed for proper current regulation, and an internal ADC and FBO feedback pin works with an external DC/DC converter to reduce driver power dissipation in large or high-brightness matrix displays.
It also supports external PMOS operation for additional thermal optimization, which moves high-side switching dissipation outside the IC package into external FETs and PCB copper, Lumissil said.
Other features include spread-spectrum PWM clocking, phase-delay control, and staged switching to help reduce supply ripple, EMI emissions, and audible-noise risk in high-brightness or high-duty-cycle ISD lighting applications; and diagnostic, protection, and communication-integrity features including LED open/short detection, ADC-based monitoring, overcurrent protection, UVLO protection, thermal shutdown, and CRC error detection.
Lumissil addresses 48-V automotive systems with the introduction of the IS32LT3962 dual-channel LED controller. By using the IS32LT3962, as automotive lighting shifts from 12-V to 48-V systems, lighting designers can achieve improved power efficiency, reduced thermal stress, and lower wiring harness cost and weight, according to the company.
The IS32LT3962 drives two independent high-voltage LED strings for automotive applications such as high-/low-beam headlights, DRLs, and turn signals and enables lamp driver modules to support two functions (e.g., high beam and low beam) with a single IC to reduce space. The dual-output channel enables independent channel brightness control, with combined analog and internal/external PWM dimming for more compact lighting solutions.
The LED controller supports a wide, 5-V to 80-V input/output range for 24-V to 48-V battery systems and delivers flexibility with buck, buck-boost, SEPIC, or boost topologies on each channel. Other features include dual analog dimming pins to enable LED binning and thermal current roll-off using an external NTC, programmable undervoltage current reduction, and spread-spectrum operation combined with 180° phase shifting to help reduce system-level EMI.
The IS32LT3962 is housed in a compact WFQFN-32 package with an exposed pad for enhanced thermal dissipation. The operating temperature range is –40°C to 125°C Automotive Temperature Grade 1.
Melexis recently announced the launch of the MLX81119, an 18-channel LIN RGB LED controller with an integrated DC/DC converter. This LED controller is designed to simplify and optimize automotive lighting systems.
The MLX81119, housed in a 5 × 5-mm QFN32 package, is powered by Melexis’s 16-bit MCU, with an integrated memory subsystem that includes 32 KB of flash, 13.5 KB of ROM, and 4 KB of RAM to support the application, LED calibration coefficients, and additional system data. It is designed to reduce power dissipation, external components, and space requirements in dense vehicle applications such as door panels, dashboards, and charge port lighting by generating the LED supply voltage locally on the chip.
Simplifying the external power stage, the LED controller operates with as few as two capacitors and a single inductor, eliminating the need for a separate DC/DC controller and associated passives. This design reduces component count and PCB area for more compact lighting modules and easier integration in space-constrained locations.
In conventional architectures, supplying LEDs via external DC/DC converters increases heat generation, component count, and layout complexity, making it harder to meet physical, efficiency, and thermal constraints as automakers increase lighting deployments to meet growing requirements for new functionality, personalization, and brand differentiation, according to Melexis.
The 18-channel MLX81119 addresses these challenges by integrating a 1-A DC/DC converter that generates an optimized local LED supply voltage, programmable between 2.5 V and 6 V. This means the LED controller does not dissipate excess voltage as heat. It dynamically adapts the LED supply to the active color mix and operating conditions to reduce power losses and thermal stress, according to the company, which is not achievable with fixed external DC/DC converter solutions.
The MLX81119 features 18 low-side current sources configurable up to 60 mA and independent 16-bit PWM control. It supports up to six RGB LEDs per device, enabling smooth color transitions and advanced lighting animations, and provides built-in direct and indirect temperature sensing that allows active compensation across all channels, so color points remain stable over the full automotive temperature range.
The MLX81119 integrates a complete LIN system, including transceiver and protocol handler, fully compliant with LIN 2.x and SAE J2602. Developed according to ISO 26262, the device supports up to ASIL-B implementations.
Novosense Microelectronics has expanded its portfolio of high-performance LED driver ICs for exterior and interior lighting with several new series. These devices feature high-side and low-side linear drivers, as well as integrated MCU solutions for RGB/RGBW ambient control, and deliver precise current regulation, advanced diagnostics, and robust thermal management for safer, more energy-efficient, and customizable lighting systems.
The lineup includes the NSL21912/16/24 12-, 16-, and 24-channel high-side linear LED drivers, NSL23716x 16-channel low-side linear LED driver, NSL2163x linear LED driver with thermal balancing, and NSUC1500 ambient lighting driver system-on-chip.
The NSL21912/16/24 series devices are automotive high-side LED drivers that deliver 100 mA per channel with 12-bit PWM dimming. They support automatic thermal sharing via VS shunt resistors for higher thermal performance. Other features include configurable LED fault detection, integrated E2PROM for fail-safe functions, a UART interface up to 2 Mbits/s, and optional ASIL-B functional-safety support.
The NSL23716x 16-channel automotive low-side LED driver delivers 100 mA per channel and 12-bit independent PWM dimming. It integrates programmable thermal derating, LED open-/short-circuit detection, and overheat protection with automatic shutdown. It also incorporates built-in OTP memory that supports fail-safe safety functions, and an optional CAN PHY interface eliminates the need for an external transceiver, simplifying design and improving system reliability.
The NSL2163x three-channel automotive linear LED driver provides up to 200 mA per channel and operates directly from a 5-V to 40-V battery supply. The device supports thermal sharing via external shunt resistors and integrates LED open-/short-circuit detection with thermal shutdown for enhanced system reliability. It offers an optional, low-power EN-pin version.
The highly integrated NSUC1500 IC for ambient lighting integrates an Arm Cortex-M3 core and four-channel high-precision current-mode LED drivers. The device provides 16-bit independent PWM dimming and 6-bit analog dimming capabilities. It enables more accurate dimming and color-mixing control while compensating for lumen depreciation, Novosense said. The NSUC1500 is compliant with the AEC-Q100 Grade 1 and CISPR 25 Class 5 EMC standards.
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