Principal Digital (mixed-signal) Architect

Job Title

Principal Digital (mixed-signal) Architect

Role Summary

Lead the digital architecture for high-speed photonic mixed-signal communication chips (Passage product family). Define system-level digital designs, specify interfaces to AMS/photonic blocks and firmware/software, produce architectural specifications, and work with vendors and customers to deliver products from concept through high-volume production.

Report to the Chief Scientist and collaborate closely with digital, analog, photonic, test, RTL, DV, and software teams to validate designs and define product and technology roadmaps.

Experience Level

Senior — expects 12+ years of industry experience (system/chip architecture and product development for high-speed mixed-signal or photonic communications).

Responsibilities

Primary responsibilities include ownership of digital architecture and cross-disciplinary collaboration from architecture to production.

• Own digital architecture for the Passage product across concept, design, and high-volume production.
• Define system-level digital designs integrating AMS and photonic components (drivers, receivers, SerDes, ADC/DAC, modulators, detectors).
• Collaborate with product management to set technological and product roadmaps.
• Work with customers and top-tier semiconductor partners at the system architecture level during development.
• Coordinate with RTL and DV teams to enable block-level implementation and verification.
• Validate hardware with test/validation engineers and compare results to simulation.
• Author and review architecture specifications; identify risks and mitigation strategies.

Requirements

Must-have technical skills and demonstrated delivery experience; preferred skills listed separately.

• 12+ years of relevant industry experience (see Experience Level); proven record delivering high-volume silicon and understanding of silicon product development flow.
• In-depth knowledge of power-efficient digital design flows for high-speed AMS electronics and digital circuit design for high-speed analog/photonic links (device bring-up, control, DSP).
• Experience specifying and integrating SerDes, ADC/DAC, high-speed drivers/receivers, and complex AMS/photonic interfaces at the system level.
• Strong problem-solving skills for ambiguous technical challenges and clear customer-facing communication.
• Experience working directly with vendors and customers; ability to represent technical leadership externally.
• Ability to produce detailed architectural documents and coordinate cross-functional execution.
• Capacity to comply with applicable U.S. export control laws.

Nice-to-have / preferred:

• Understanding of SerDes PCS, equalization, and forward error-correction schemes.
• Proficiency with CAD tools, SPICE, IBIS-AMI simulators, and programming/scripting (MATLAB, Python, etc.).
• Experience collaborating in cross-disciplinary teams and building programmatic processes.

Education Requirements

Master's degree in Electrical or Computer Engineering required. (Posting specifies a Master’s degree in Electrical or Computer Engineering; 12+ years of experience expected.)

About the Company

Company: Lightmatter

Headquarters: Boston, Massachusetts, USA

Lightmatter develops photonic AI data-center infrastructure and optical chips for extreme-scale AI and HPC. The company invented the Passage 3D‑stacked photonics engine to provide high-bandwidth, low-latency interconnects across large-scale processors and raised $400M in Series D financing at a reported $4.4B valuation.