Celestial AI Inc., a startup developing photonics technology for artificial intelligence applications, has raised $56 million in funding to support its engineering efforts.

Sunnyvale, California-based Celestial AI announced the investment this morning. Koch Disruptive Technologies led the investment with participation from Temasek’s Xora Innovation fund, Tyche Partners, Merck & Co. Inc.’s venture fund and IMEC XPand. The Engine and Fitz Gate, which are active in the startup ecosystems of MIT and Princeton University, respectively, contributed as well. 

Celestial AI is developing an accelerator chip called Orion that’s designed to speed up machine learning applications. What sets the chip apart from the numerous existing AI accelerator products on the market is a technology dubbed Photonic Fabric. The technology transports data among the Orion chip’s circuits in the form of light, rather than in the form of electricity as most processors do.

According to Celestial AI, one of Photonic Fabric’s main advantages over traditional systems is that it requires less power. Depending on the application a chip is running, data movement can account for a significant portion of the chip’s power consumption. Lowering the amount of electricity necessary to run AI workloads helps reduce operating costs.

Another, equally significant benefit is that reducing the amount of electricity necessary for data movement can indirectly boost chip performance. That’s another selling point through which Celestial AI hopes to set its Orion accelerator chips apart from rivals.

Chips generate heat while carrying out calculations. The more electricity a processor uses, the more heat it generates. As a result, the amount of electricity that the processor can use has to be limited to prevent it from reaching excessive temperatures that may cause a malfunction.

Because of the need to avoid excessive temperatures, every chip can only draw a certain maximum amount of electricity. A part of this electricity has to be used for computing tasks. Another part goes toward moving data between the chip’s circuits. Reducing the amount of power needed for data movement between circuits, which is what Celestial AI’s optical technology accomplishes, allows more electricity to be directed to computing tasks, thereby making it possible to increase performance.

Transporting data as light rather than as electricity can also increase performance in another way. Light travels faster than electricity, which means information arrives at its destination faster and processing can begin sooner. 

Celestial AI’s Orion machine learning accelerator chip combines its optical technology with electronic compute components. The startup reportedly plans to sell its chips as part of two products. The first is a PCIe card that can be attached to servers to boost their processing capacity, while the other is an appliance featuring multiple Orion chips.

“Celestial AI’s hybrid photonic-electronic platform allows us to leverage the complementary strengths of electronics for high-performance, high-precision computing and photonics for high-speed, low-power, high-bandwidth data movement,” stated Celestial AI founder and Chief Executive Officer David Lazovsky. “Our competitive differentiation will increase with time, as AI model complexity increases, driving increased data movement.”

Celestial AI says that its optical technology can be used to transport data not only between the circuits of a processor, but also from one chip to another. Large-scale AI applications usually run on multiple chips. The data being processed by an AI application regularly travels between the chips on which it runs, a task that Celestial AI’s technology can accelerate to speed up computations. 

Celestial AI will use the proceeds from its new funding round to grow its engineering team. The startup also plans to invest in “product development and strategic supplier” partnerships. One of the companies with which Celestial AI has been working is Broadcom Inc., a major supplier of networking chips for data centers.

Celestial AI is one of several startups developing chip technology to make data movement more efficient. A number of other companies are also using optical approaches to transport information faster. Cerebras Systems Inc., meanwhile, is taking a different approach. Instead of sending data in the form of light to increase the speed at which information can travel, Cerebras’ technology reduces the distance that the information has to cover. 

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