---
title: 'Principal Digital (mixed-signal) Architect at Lightmatter'
canonical: 'https://feeny.ai/job/principal-digital-mixed-signal-architect-lightmatter-boston-g2fj4k74sr48'
type: 'job'
last_seen: '2026-09-04'
---

# Principal Digital (mixed-signal) Architect at Lightmatter

- **Company:** Lightmatter
- **Location:** Boston, MA / Mountain View, CA
- **Compensation:** $217k–$325k
- **Posted:** 2025-12-05
- **Last confirmed live:** 2026-09-04
- **Apply:** https://boards.greenhouse.io/lightmatter/jobs/5020803008?gh_jid=5020803008

## Job description

Lightmatter is leading the revolution in AI data center infrastructure, enabling the next giant leaps in human progress. The company invented the world’s first 3D-stacked photonics engine, Passage™, capable of connecting thousands to millions of processors at the speed of light in extreme-scale data centers for the most advanced AI and HPC workloads.

Lightmatter raised $400 million in its Series D round, reaching a valuation of $4.4 billion. We will continue to accelerate the development of data center photonics and grow every department at Lightmatter!

If you're passionate about tackling complex challenges, making an impact, and being an expert in your craft, join our team of brilliant scientists, engineers, and accomplished industry leaders.

Lightmatter is (re)inventing the future of computing with light!

We are hiring a Principal Digital Architect for high-speed photonic (mixed-signal) communication chips. The selected candidate will partner with external facing teams at Lightmatter and the internal engineering team to deliver groundbreaking products to the market. As an architect, you will provide detailed technical documents that describe what needs to be built to the engineering team. This will require a solid understanding of process technology, state of the art in chip design, and clear communication skills. You will represent the company externally at technical conferences as an example of our technical leadership.

In this role, you will be defining the architecture of the digital circuits that enable a ground-breaking photonic-based communication fabric. Your work will not only enable the AMS/photonic devices at low-level but also enable the necessary interfaces with the firmware/software. You will interact directly with our vendors and our customers. You will also define the product and technological roadmaps along with suitable design and verification methodologies.

You will report directly to the Chief Scientist, but you will also work closely with our digital, analog, photonic, and software teams. We are particularly looking for someone with expertise in architecting digital circuits to enable high-speed AMS circuits, with a strong preference for someone with experience in photonic circuits.

Join a tight-knit team where each individual’s contributions directly influence the success of the company and product. You'll have the opportunity to build a new kind of computer from the ground up and to solve groundbreaking challenges along the way. Work with people who love to build and who thrive in technically diverse environments where great ideas are prioritized.

## Responsibilities

- Be the digital architecture owner of Lightmatter’s Passage product.
- Responsible for the digital architecture from initial concept through high-volume production. Work closely with the technical program manager(s) to plan, organize, and execute.
- Lead direct collaboration with top tier semiconductor customer(s) throughout the product development process at the system architecture level.
- Architect and specify system level digital designs integrating complex AMS and photonic circuits. These circuits include high-speed drivers and receivers, SerDes, ADC/DAC, photonic modulators and detectors.
- Collaborate with the product team to develop our future technological and product roadmap.
- Work closely with test and validation engineers to validate hardware against simulation prediction.
- Actively collaborate with the RTL and DV teams to enable block-level implementation and verification, respectively.
- Author, review, and validate architectural specifications.
- Identify possible improvements as well as possible pitfalls (including mitigation strategies) around executing the proposed architectures.

## Qualifications

- 12+ years and a Masters’ degree in Electrical or Computer Engineering
- In-depth knowledge of power-efficient digital design flow for high-speed AMS electronics, preferably on photonic communication channels.
- Proven track record of delivering successful high-volume silicon in the market. Also, proven understanding of silicon product development flow.
- In-depth knowledge of digital circuit design in a high-speed analog/photonic link, including device bring-up, control, and digital signal processing.
- Demonstrated strong problem solving skills specifically pertaining to problems that do not have obvious solutions.
- Demonstrated strong customer communication, with timely responses and consistently positive feedback

## Preferred Qualifications

- Understanding of SerDes PCS layer and equalization along with forward error-correction schemes.
- Ability and desire to collaborate in a cross-disciplinary team.
- Power user of multiple development tools, including CAD tools, SPICE simulators, IBIS-AMI simulators, and general programming languages (e.g., MATLAB or Python).
- Willing and able to learn quickly. Self-starter with a “no task is too big or small” attitude.
- Innovative and flexible; realizes that a one-size-fits-all approach will not always solve the problem at hand.
- Data-driven and analytical; translates numbers into actionable strategies.
- Process-oriented and programmatic: builds structure through processes that can be relied upon across the organization.

We offer competitive compensation. The base salary range for this role determined based on location, experience, educational background, and market data.

Salary Range: total compensation goes beyond base salary, it also includes a new hire equity grant, annual performance-based equity, and other rewards that recognize your impact and contribution. $217,000—$325,000 USD

## Benefits

- Comprehensive Health Care Plan (Medical, Dental & Vision)
- Retirement Savings Matching Program
- Life Insurance (Basic, Voluntary & AD&D)
- Generous Time Off (Vacation, Sick & Public Holidays)
- Paid Family Leave
- Short Term & Long Term Disability
- Training & Development
- Commuter Benefits
- Flexible, hybrid workplace model
- Equity grants (applicable to full-time employees)

Benefits eligibility may vary depending on your employment status and location. Lightmatter recruits, employs, trains, compensates, and promotes regardless of race, religion, color, national origin, sex, disability, age, veteran status, and other protected status as required by applicable law.

Export Control

Candidates should have capacity to comply with the federally mandated requirements of U.S. export control laws.

## About Lightmatter

## Company Overview
- **One-liner**: Lightmatter builds photonic interconnects and computing infrastructure to eliminate bandwidth bottlenecks in AI and high-performance computing, enabling the next era of AI scaling.
- **Entity Type**: Private (Series D, $850M total funding)
- **Headquarters**: Mountain View, California, USA
- **Founded**: 2017
- **Founders**: Nicholas Harris, PhD (CEO), Darius Bunandar, PhD (Head of Machine Learning), and a third co-founder (Chief Scientist)

## Core Business
- **Primary industry**: Silicon Photonics / AI Infrastructure / Semiconductor
- **Target customers**: Hyperscale data center operators, AI labs (training frontier models), cloud service providers, and enterprise AI teams
- **Mission or purpose**: To make computers keep getting better by using light instead of electricity for data movement, solving the fundamental bandwidth bottleneck that limits AI scaling.

## Products & Services
- **Passage™ Platform**: A family of 3D-stacked silicon photonics interconnects (NPO, OBO, 2D/3D CPO, 3D interposers) that provide "Edgeless I/O"—unlimited bandwidth scaling for AI supercomputers. Key variants include:
  - **Passage M1000 EVK**: Rack-level 3D photonic interposer delivering 114 Tbps across a 4,000 mm² footprint.
  - **Passage L200**: Designed for frontier-scale training, supporting 32–64 Tbps aggregate bandwidth via co-packaged optics (112G PAM4).
  - **Passage L20**: Accelerates optics integration with 12.8 Tbps aggregate bandwidth and 4x pluggable density.
  - **Passage EVK100**: High-bandwidth bidirectional link at 3.2 Tbps per fiber, 1.9 pJ/bit.
  - **Passage EVK50**: 16-wavelength bidirectional link at 800 Gbps per fiber, 2.6 pJ/bit.
- **Guide® Light Engines**: Very Large Scale Photonics technology—a universal light source (hundreds of lasers and photonics components on a single chip) designed to power co-packaged optics across the entire photonics industry.

## Market Standing
- **Valuation**: $4.4 billion (as of October 2024)
- **Key Metric**: $850M total funding raised
- **Notable Investors/Partners**: TSMC, GlobalFoundries, Tower Semiconductor (manufacturing partners); Amkor, ASE (packaging partners); NVIDIA (joined NVLink Fusion ecosystem); standards bodies including Ultra Ethernet, UALink, JEDEC, OIF, IEEE, OCP, and the Advanced Photonics Coalition.
- **Growth Signals**: First-mover in category-defining photonic interconnects; multiple generations of production-ready technology (not vaporware); reference platforms in customer hands; 100,000+ GPU cluster capability; world-first 16-wavelength bidirectional optical DWDM link on standard single-mode fiber (8x leap in bandwidth density); partnerships with top foundries ensure high-volume manufacturing.

## Competitive Advantages
- **Edgeless I/O architecture**: Eliminates the physical chip-perimeter constraint that limits electrical interconnects, enabling bandwidth to scale without bound.
- **Fundamentally better physics**: Photons travel without resistive loss, cross paths without interference, and carry multiple signals on a single fiber—far more efficient than electrons.
- **Deep vertical integration**: From photonic chip design to light engines (Guide) to complete interconnect platforms (Passage), with proprietary 3D stacking technology.
- **Decade-scale roadmap**: Continued bandwidth scaling (114 Tbps today, 1+ Pbps tomorrow) with production-ready silicon validated at scale.
- **Ecosystem lock-in**: Standards body leadership and partnerships with NVIDIA, TSMC, and hyperscalers create high switching costs.

## Strategic Focus
- **Scale AI infrastructure**: Enable 100,000+ GPU clusters for trillion-parameter models, solving the interconnect bottleneck that currently strands hundreds of millions in compute capacity.
- **Productize photonics**: Move from reference platforms to volume production across Passage and Guide families, targeting both training and inference workloads.
- **Expand ecosystem**: Deepen partnerships with hyperscalers, AI labs, and chipmakers (e.g., NVIDIA NVLink Fusion) to make photonic interconnects the default for next-gen data centers.
- **Hire across all functions**: Actively growing engineering, research, sales, and operations teams to scale the company.

## Why Work Here
- **Mission-driven impact**: Work at the intersection of photonics, AI, and semiconductor engineering to solve the most critical bottleneck in AI—data movement. Your work directly enables frontier models and trillion-parameter training.
- **World-class team**: Colleagues from MIT, Caltech, Stanford, and UC Berkeley; published in Nature, Science, ISSCC, ISCA; 100+ patents; team members contributed to black hole simulation software for the Academy Award-winning movie *Interstellar*.
- **Cutting-edge technology**: Not research, not vaporware—multiple generations of production-ready photonic chips in customer hands, with a decade-scale roadmap.
- **Locations**: Mountain View, CA (HQ); Boston, MA; Hsinchu, Taiwan; Toronto, Canada.
- **Benefits**: 401(k), generous vacation policy and holidays, commuter benefits, happy hours, and a strong learning culture (peer-to-peer knowledge sharing across electronics, photonics, machine learning, and more).
- **Culture**: "We are one Lightmatter"—collaborative, cross-disciplinary, and focused on solving hard problems at scale.

## Sources
1. [lightmatter.co/about](https://lightmatter.co/about/)
2. [lightmatter.co](https://lightmatter.co/)
3. [lightmatter.co/people/careers](https://lightmatter.co/people/careers/)
4. [lightmatter.co/people](https://lightmatter.co/people/)
5. [linkedin.com/company/lightmatter](https://www.linkedin.com/company/lightmatter)

## Other roles at Lightmatter

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- [Senior Account Manager](https://feeny.ai/job/senior-account-manager-lightmatter-mountain-view-zcefyvftztp2) — Mountain View, CA
- [Staff /Sr Staff Laser Module & Systems Characterization Engineer](https://feeny.ai/job/staff-sr-staff-laser-module-systems-characterization-engineer-lightmatter-1wcg5m40jtae) — Mountain View, CA
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