Optoelectronics leader focuses on Micro LED optical communications

Recently, ams Osram announced that it is collaborating deeply with data center equipment manufacturers to promote the implementation and adaptation of MicroLED technology in the field of optical interconnection, including developing high-frequency data transmission drive circuits, optimizing micro-packaging solutions, and ensuring good interoperability with commercial optical connectors, optical cables and optical fibers.

ams and Osram combine Micro LED automotive headlight technology experience. Although this technology route is not the core track of AI innovation, adaptive high-beam headlight technology has been market-proven, and the optical connection architecture used in this solution can provide a feasible path for data center operators to solve core pain points such as network bandwidth expansion, energy efficiency improvement, and reliability enhancement.

This article will start from the underlying logic of the technology and provide an in-depth analysis of the intrinsic relationship and industrial reference value between automotive headlight technology and AI data centers.

Trend of Micro LED optical communication replacing copper cables

The explosive growth in demand for AI training and inference has led equipment manufacturers to upgrade system computing power to the extreme. Currently, xPU series accelerators represented by GPU and NPU have achieved efficient processing of AI data. The computing link itself is no longer the core bottleneck. What really restricts the release of computing power is the efficiency of data transmission between xPUs, between xPUs and memory, and even between servers in the rack.

Traditional copper interconnects are widely used due to their cost and integration convenience advantages, but their expansion bottlenecks have become increasingly prominent: in transmission scenarios where the AI computing system can be up to 30 meters long, copper interconnects require higher energy consumption and more complex signal balancing and conditioning circuits to suppress electromagnetic interference, which directly leads to a significant increase in link power consumption and heat, severely limiting further improvements in bandwidth density, system energy efficiency, and reliability.

To this end, data centers have begun to turn to optical interconnection technology, whose technological origins can be traced back to the Internet backbone network. Operators responsible for intercontinental traffic transmission have already maximized the throughput of single cables by relying on submarine optical cables with limited numbers and extremely high laying and maintenance costs. The current single channel rate of intercontinental optical transmission networks has reached 1.6Tbit/s.

The core idea of this type of "high-speed narrowband" solution is to maximize the potential of data transmission within a single optical channel. However, the high-frequency system itself has shortcomings such as complex architecture, high power consumption, and high cost. More importantly, a single link has become a single point of failure that affects the entire system, directly threatening the overall system availability. As the speed and throughput of single channels continue to increase, implementation difficulty and cost increase exponentially, and the expansion ceiling of the "high-speed narrowband" architecture has gradually emerged.

The root cause is that Internet infrastructure is subject to high cable laying and operation and maintenance costs, and has to pursue maximizing single-cable throughput; in the data center scenario, this hard constraint does not exist.

Against this background, the data center industry is setting its sights on a new technological route: abandoning the blind pursuit of "high-speed narrowband" and instead adopting the "low-speed broadband" idea - replacing a single ultra-high-speed link with hundreds or even thousands of low-speed parallel optical channels to achieve higher overall bandwidth while using simpler, low-cost, low-speed devices.

In this type of system architecture, hundreds of Micro LEDs can be used at the data transmitter to replace a single high-power laser in the Internet backbone network. However, since communication equipment manufacturers have never built a parallel optical transmission system composed of hundreds or thousands of Micro LED emission units before, the "low-speed broadband" solution is still a cutting-edge direction that has not been fully verified in the data center scenario.

Micro LED arrays have been verified in the automotive lighting market

The core difficulty of the "low-speed broadband" architecture is to highly integrate hundreds of light-emitting units near the server processor and storage module.

Faced with the continuously growing demand for AI computing power, data center operators have put forward stringent reliability requirements for such micro light sources to operate stably and uninterrupted throughout the year. Chip-level arrays composed of thousands of Micro LEDs have already completed rigorous verification in the automotive market with complex working conditions. This is the key inspiration that automotive headlight technology brings to the data center industry.

ams-Osram's EVIYOS™ adaptive high-beam light source is the culmination of this technical capability, and the product has been implemented in multiple models.

It is understood that its single EVIYOS chip integrates up to 25,600 Micro LED array units, with a single pixel size only equivalent to half the diameter of a hair, and uses a CMOS driver chip to achieve a 22.0mm×17.5mm miniaturized system-in-package.

Figure 1: EVIYOS products integrate microLED arrays and driver circuits into compact packages

25,600 pixels can be independently addressed and controlled, allowing the headlights to accurately project complex adaptive light patterns on the road. This original Micro LED and CMOS driver integration technology has won the German "Digital Light" Future Award, and related products have also fully verified their high reliability and environmental robustness in mass-produced models.

Today, this core technology derived from automotive lighting is being migrated and optimized and applied to ultra-high-bandwidth optical interconnect systems in AI data centers.

The evolution of Micro LED car lights to optical interconnection

For optical interconnect applications, related devices use the same manufacturing process as automotive headlights, but there are key differences in architectural design: Micro LEDs for car lights are high-density monolithic arrays, while data communication scenarios require Micro LEDs to be debonded, separated from the wafer and then mounted on a substrate, so that each emitting unit can be independently connected to an optical fiber or optical waveguide, and the substrate can be further integrated into the target CMOS. wafer.

Figure 2: High-speed optical link MicroLED manufacturability implementation path

With the miniaturization advantages of Micro LED, data communication transceivers based on this technology can achieve extremely high bandwidth density. According to ams-OSRAM internal test data, under 10-meter full link conditions, the Micro LED transmitter can achieve a single-channel 3.0Gbit/s transmission rate, with a unit power consumption of less than 2pJ, while meeting the 10⁻¹⁵ bit error rate required by industry standards.

Replacing a single ultra-high-speed link with hundreds of parallel channels also brings multiple core values in the data center scenario to AI equipment manufacturers:

Higher reliability: Micro LED can support multi-redundant channel design, and a single transmitting unit failure can achieve non-inductive failure, with the backup channel automatically taking over the transmission task.

Better energy efficiency: Under the "low-speed broadband" architecture, the operating frequency of the transmitting unit is about 1GHz, which is much lower than the traditional backbone network high-frequency laser solution. The power consumption is significantly reduced, while reducing heat generation, leaving a looser thermal design budget for the system.

Simplified architecture: Traditional "high-speed narrowband" solutions require serialization and deserialization of parallel data, while the "low-speed broadband" architecture equipped with ams-OSRAM Micro LED has native parallel characteristics and can eliminate the need for complex and high-cost SerDes modules.

ams-OSRAM promotes Micro LED optical communications

As the only manufacturer in Europe with large-scale mass production capabilities of Micro LED, ams-OSRAM's production capacity and processes have been fully verified by the market, and it has continued to deliver EVIYOS series products to the automotive field in batches since 2023.

Currently, ams and Osram are collaborating deeply with data center equipment manufacturers to promote the implementation and adaptation of MicroLED technology in the field of optical interconnection, including developing high-frequency data transmission drive circuits, optimizing micro-packaging solutions, and ensuring good interoperability with commercial optical connectors, optical cables and optical fibers.

During this technological evolution, partner manufacturers can fully rely on ams-OSRAM's optical system integration capabilities. ams Osram has the mass production capabilities of both MicroLEDs and photodiodes, and can play a core supporting role in the development of fully integrated optical data transmission systems.