DustPhotonics raises funding for 800G and 1.6T modules

• DustPhotonics has raised $24 million in funding.
• The start-up has taped out its 200 gigabit-per-lane optical chip.
• DustPhotonics expects the 1.6-terabit module market to ramp, starting year-end.

Ronnen Lovinger

DustPhotonics, which develops chips for transmit optical sub-assemblies (TOSAs) for 400 and 800-gigabit pluggable optical modules, has raised $24 million. The funding extends its Series B funding round.

"When you start ramping up products, you have to iron out the creases around supply chain, production, and everything else," says Ronnen Lovinger, CEO of DustPhotonics.

DustPhotonics has several customers and a backlog of orders for its 400 and 800-gigabit photonic integrated circuits (PICs). The company has also taped out its 200 gigabit-per-lane chip and will have products later this year.

800-gigabit PICs

DustPhotonic's products include the Carmel-4-DR4, a 400-gigabit DR4 PIC, and several variants of its 800-gigabit Carmel-8.  

"Most of our customers and engagements are interested in the 800-gigabit applications," says Lovinger.

DustPhotonics has developed a way of attaching a laser source to its silicon photonics chip with sub-micron accuracy. The company uses standard off-the-shelf continuous-wave lasers operating at 1310nm.

The efficiency of the laser-attach scheme means one laser can power four channels, or two lasers can be used for a DR8 design, reducing cost and power consumption.

At the ECOC show last October, DustPhotonics unveiled three 800-gigabit Carmel-8 products. The products include a DR8 with a reach of 500m, a 2km DR8+, and an 800-gigabit 'lite' version that competes with 100-gigabit VCSEL designs and only uses one laser. Several customers are considering the Carmel-8-Lite for Ethernet and PCI Express applications.

Immersion cooling in action. Source: DustPhotonics. 

Immersion cooling

DustPhotonics has also developed an 800-gigabit optical engine, the Carmel-8-IMC, for immersion cooling applications.

Immersion cooling is used to remove heat from equipment in a data center. "You're immersing the entire system into liquid," says Lovinger.

The heat-removal technique is not new, but it is only now being adopted due to the power consumption and heat generated by the latest AI hardware.

Nvidia is expected to announce that its next-generation AI system using the Blackwell B100 graphics processing unit (GPU) will adopt immersion cooling.

DustPhotonics' laser-coupling scheme means its optical engine is inherently suited to immersion cooling. "We have an advantage with our laser attach and the butt-coupling of fibres," says Lovinger. "We don't have any air gaps, which makes our designs ready for immersion."

DustPhotonics is working with a company to show the capabilities of the immersion cooled Carmel-8-IMC.

200-gigabit optical

DustPhotonics has a highly stable silicon-photonics modulator that does not need to be temperature-controlled and operates at 200 gigabits per lane.

Developing a 200 gigabit-per-lane transmit chip means that DustPhotonics can address a 4-lane 800-gigabit DR4 and an 8-lane 1.6-terabit DR8 modules.

Lovinger says that many driver and digital signal processing chip companies already offer 800 gigabit/ 1.6-terabit chips. Thus, he sees the advent of 1.6 terabit modules as straightforward once its TOSA design is ready.

"Once we have 200 gigabits-per-lane, it takes us to 1.6 terabits and, in some configurations, 3.2 terabits," says Lovinger. "We see the 1.6-terabit market starting at the end of this year and ramping in 2025."

Lovinger says the progress of pluggable modules is postponing the need for co-packaged optics. That said, the company says it has the technologies needed to address co-packaged optics when the market finally needs it.

Manufacturing

DustPhotonics is working with foundry Tower Semiconductors as it goes to production.

"Having a strong fab partner is very important for silicon photonics," says Lovinger, who views Tower as a leading silicon photonics foundry. "We have been working with Tower for five years, and they have been a strong partner." DustPhotonics is using several partners for device assembly.

DustPhotonics is headquartered in Israel and has 50 staff, 37 of whom are in R&D. Investors in the latest funding round include Sienna Venture Capital, Greenfield Partners, Atreides Management, and Exor Ventures. 

Lovinger will attend the OFC show later this month for meetings with customers and prospects. "It is always good to see so many customers under the same roof," he says.