8 March 2023
Avicena partners with ams OSRAM on production of ultra-low-energy chip-to-chip optical interconnects
Avicena Tech Corp of Sunnyvale, CA, USA (which develops ultra-low-energy optical links based on micro-LEDs) has partnered with ams OSRAM GmbH of Premstaetten/Graz, Austria and Munich, Germany to develop high-volume manufacturing of gallium nitride (GaN) micro-LED arrays for its LightBundle communication architecture.
The need for next-generation computing power is driven by strong AI/ML (artificial intelligence/ machine learning) and HPC (high-performance computing) application demand – for products like ChatGPT, DALL-E, autonomous vehicle (AV) training, and many others. Attempts to scale existing architectures are running into physical limits, leading to slower-throughput-growth, power-hungry and hard-to-cool systems. The LightBundle architecture is said to unlock the performance of xPUs, memory and sensors, removing key bandwidth and proximity constraints while simultaneously offering an order-of-magnitude reduction in power consumption.
“We acquired our fab from Nanosys in October to accelerate our development efforts and support low-volume prototype manufacturing,” notes Avicena’s founder & CEO Bardia Pezeshki. “However, we are addressing very sizeable markets requiring high-volume manufacturing. We are very pleased to partner with one of world’s top GaN LED companies to provide a path to satisfy the expected high volumes required by our customers, including hyperscale data-center operators and the world’s leading IC companies,” he adds.
“Avicena’s LightBundle technology provides an opportunity for GaN micro-LEDs to impact numerous key applications including HPC, AI/ML, sensors, automotive and aerospace,” says Robert Feurle, executive VP & managing director, OS business unit at ams OSRAM. “As a global leader in GaN LEDs, we are excited to partner with Avicena to transform these very large and important markets.”
Today’s high-performance ICs use SerDes-based electrical links to achieve adequate IO density. However, the power consumption and bandwidth density of these electrical links degrade quickly with length. Conventional optical communications technologies developed for networking applications have been impractical for inter-processor and processor–memory interconnects due to their low bandwidth density, high power consumption, and high cost. Moreover, co-packaging existing laser sources with hot application-specific integrated circuits (ASICs) causes reliability problems unless external laser sources (ELS) are used, which increases complexity and cost.
LightBundle links use densely packed arrays of GaN micro-LEDs to create highly parallel optical interconnects with typical throughputs of >1Tb/s at energies of <1pJ/bit. A LightBundle cable uses a highly multi-core multi-mode fiber to connect a GaN micro-LED transmitter array to a matching array of silicon photodetectors (PDs). Arrays of hundreds or thousands of LightBundle’s micro-LEDs and PDs can be integrated with standard CMOS ICs, enabling the closest integration of optical interconnects with electrical circuits. In addition to high energy efficiency and high bandwidth density, these LightBundle links also exhibit low latency since the modulation format of the individual links is simple NRZ instead of PAM4 (which is common in many modern optical links but has the disadvantage of higher power consumption and additional latency).
Avicena says that the parallel nature of LightBundle is well matched to parallel chiplet interfaces like UCIe, OpenHBI and BoW, and can also be used to extend the reach of compute interconnects like PCIe/CXL and HBM/DDR/GDDR memory links, as well as various inter-processor interconnects like NVLink with low power and low latency.
Avicena at OFC 2023
Avicena is showing the LightBundle architecture and technology in booth #3950 at the Optical Fiber Communication Conference & Exhibition (OFC 2023) in San Diego, CA, USA (7–9 March).