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SI/PI Engineer

About Celestial AI

As Generative AI continues to advance, the performance drivers for data center infrastructure are shifting from systems-on-chip (SOCs) to systems of chips. In the era of Accelerated Computing, data center bottlenecks are no longer limited to compute performance, but rather the system’s interconnect bandwidth, memory bandwidth, and memory capacity. Celestial AI’s Photonic Fabric™ is the next-generation interconnect technology that delivers a tenfold increase in performance and energy efficiency compared to competing solutions.

The Photonic Fabric™ is available to our customers in multiple technology offerings, including optical interface chiplets, optical interposers, and Optical Multi-chip Interconnect Bridges (OMIB). This allows customers to easily incorporate high bandwidth, low power, and low latency optical interfaces into their AI accelerators and GPUs. The technology is fully compatible with both protocol and physical layers, including standard 2.5D packaging processes. This seamless integration enables XPUs to utilize optical interconnects for both compute-to-compute and compute-to-memory fabrics, achieving bandwidths in the tens of terabits per second with nanosecond latencies.

This innovation empowers hyperscalers to enhance the efficiency and cost-effectiveness of AI processing by optimizing the XPUs required for training and inference, while significantly reducing the TCO2 impact. To bolster customer collaborations, Celestial AI is developing a Photonic Fabric ecosystem consisting of tier-1 partnerships that include custom silicon/ASIC design, system integrators, HBM memory, assembly, and packaging suppliers.

Job Description:

Celestial AI is seeking an SI/PI Engineer to help develop and validate Celestial’s world-class energy efficient AI compute and photonic data transmission solutions. Self-starter who is passionate about innovation and comfortable working on the cutting edge of VLSI / RF / Optical Networking technology. The ideal candidate will be comfortable solving the technical challenges of 2.5d die / package / PCB performance optimization and develop a design -> simulate -> correlate development process for package and PCB level interconnect and power delivery. Has a strong sense of ownership, loves turning ambiguity into real outcomes and working across all engineering and product functions to deliver required solutions in a timely manner.

In this role, you will work closely with engineers responsible for analog I/O design, die physical design, photonics, packaging, PCB, and validation. You will be responsible for performing simulations and design studies and reviewing PCB, Package, and silicon layouts to ensure Celestial AI test articles and end products meet appropriate SI/PI targets while taking into account cost-effectiveness, time to market, supply chain risk, and performance tradeoffs. Additional responsibilities include resolving SI/PI issues encountered on the path to high volume manufacturing during the NPI phase and developing technology roadmaps to support the overall company product roadmap. This job will require you to have strong project management, written and verbal communication skills as well as a can-do attitude to prioritize and address issues with a very high sense of urgency. 

 

ESSENTIAL DUTIES AND RESPONSIBILITIES:

  • Use electromagnetic simulation software such as Ansys HFSS / SiWave or Cadence Sigrity Suite to perform pre and post layout simulations
  • Use layout software such as Cadence Allegro/APD viewers, Virtuoso, Klayout, etc. to review designs and modify designs for simulation
  • Use Real Time Oscilloscopes, Sampling Oscilloscopes, TDR, and VNA to verify performance, correlate models to simulation, and debug issues
  • Develop strong technical relationships within the company and externally with customers and vendors as a single point of contact for SI/PI design and manufacturing problems
  • Collaborate with industry peers and suppliers to stay abreast of industry advances and future roadmaps
  • Resolve daily technical issues with cross-functional engineering teams in a timely manner and drive for Celestial AI’s success
  • Actively manage SI/PI qualification of test articles and products, while operating within established cost and time constraints

 

QUALIFICATIONS:

  • Master’s degree or higher in Electrical Engineering or RF is preferred but not required
  • 5+ years of experience in signal/power integrity
  • Expertise with time and frequency domain simulation and measurement
  • Prior experience with high speed serdes and power delivery modelling/optimization
  • Experience with Photonics is a plus
  • Ability to deliver effective results in collaborative cross-functional teams in a fast paced startup environment

 

Location: Bay Area location is required.

 

For California location:

As an early startup experiencing explosive growth, we offer an extremely attractive total compensation package, inclusive of competitive base salary and a generous grant of our valuable early-stage equity. The target base salary for this role is approximately $160,000.00 - $185,000.00. The base salary offered may be slightly higher or lower than the target base salary, based on the final scope as determined by the depth of the experience and skills demonstrated by candidate in the interviews.

We offer great benefits (health, vision, dental and life insurance), collaborative and continuous learning work environment, where you will get a chance to work with smart and dedicated people engaged in developing the next generation architecture for high performance computing.

Celestial AI Inc. is proud to be an equal opportunity workplace and is an affirmative action employer.

 

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