THE OPPORTUNITY

Lumai is redefining how the world computes. We are an ambitious, venture-backed UK startup building a breakthrough AI accelerator for the data centre, powered by 3D optical compute. Our technology uses light rather than electricity to perform the matrix multiplications at the heart of AI inference — at speeds and scales electronics cannot reach, and at a fraction of the energy.

The performance and efficiency gains we are unlocking could reset the economics of AI infrastructure and change how intelligence scales globally.

If you want to bring genuinely new technology to market and work at the edge of what is physically possible, Lumai is where you can do it.

ABOUT LUMAI

Founded in 2022, Lumai is a University of Oxford spinout using optical processing to accelerate large language models and other transformer-based AI systems. Our team brings together optical computing, machine learning, physics, and silicon expertise.

We have raised over $15 million from leading deep-tech investors and government grants, and we are scaling quickly to deploy the fastest optical compute available anywhere. Every day here is spent on technology that did not exist five years ago. You will not be maintaining legacy systems.

THE ROLE

Every analog and mixed-signal design ultimately has to answer to silicon. As an Analog Test & Characterization Engineer at Lumai, you will bring our chips to life on the bench, bringing up new silicon, characterising analog and mixed-signal performance, and closing the loop between what was simulated and what silicon actually does.

You will work hands-on with lab equipment and custom test setups to extract accurate performance data on data converters, bias/reference circuits, and clocking IP, then work with the design team to understand and explain any gaps between measurement and simulation.





You will report to the Senior Analog/Mixed-Signal Design Lead and work closely with circuit designers, layout, and firmware/software engineers to support silicon bring-up from first power-on through full characterisation.

WHAT YOU'LL DO

Bring-Up and Characterisation

- Plan and execute silicon bring-up for new analog and mixed-signal IP, from initial power-on and functional checks through full performance characterisation.
- Develop bench test plans and set up lab equipment (oscilloscopes, spectrum and network analyzers, precision sourcemeters, ATE where applicable) to measure analog performance.
- Characterise key performance metrics for data converters (SNDR, ENOB, SFDR, INL/DNL), PLLs (jitter, phase noise), and bias/reference circuits (PSRR, drift, noise).

Correlation and Debug

- Correlate measured silicon performance against simulation and models, identifying and helping root-cause any discrepancies with the design team.
- Support debugging of unexpected silicon behaviour, working closely with circuit designers to isolate root cause at the bench.

Automation and Documentation

- Build or adapt test automation scripts (typically Python-based) to speed up repetitive bench measurements and data collection.
- Document characterisation results clearly, producing reports that inform design iteration, calibration tuning, and production test planning.
- Contribute to the transition from bench characterisation setups toward production test planning as designs mature.

WHAT WE'RE LOOKING FOR

Must-Have

- 2–6 years of experience in silicon bring-up,



bench characterisation, or analog test engineering.
- Hands-on proficiency with standard lab equipment: oscilloscopes, spectrum/network analyzers, precision sourcemeters, and similar bench instrumentation.
- Demonstrated experience correlating measured silicon performance against simulated or modelled expectations.
- Working knowledge of key analog/mixed-signal performance metrics (e.g. SNDR/ENOB for converters, jitter/phase noise for PLLs).
- Comfortable writing scripts (Python or similar) to automate bench measurements and process characterisation data.
- Methodical, detail-oriented approach to debugging discrepancies between expected and measured behaviour

Strong Preference For

- Experience characterising data converters or high-speed analog front ends specifically.
- Exposure to ATE (automated test equipment) and the transition from bench to production test.
- Familiarity with photonic or optical receiver test setups.
- Experience supporting calibration algorithm tuning based on measured silicon data.
- Prior experience at a fabless startup bringing up first-silicon on a new process node.

INTERVIEW PROCESS

Our process is four stages. An initial conversation with our HR team to understand what you want from the role and what we want from it. Two technical sessions with members of our analog design and ASIC physical design teams. Finally, an HR-team session covering scope, terms, and any final questions. We aim to move fast on candidates we are excited about; expect roughly three to four weeks end to end.

Lumai is an equal opportunity employer. We make hiring decisions on merit, scope-fit, and the strength of the working relationship we expect to build with each hire. Applications welcome from candidates of any background. If you are not sure whether you are a fit, send a note anyway.

📌 Analog Test & Characterization Engineer (España)
🏢 Lumai
📍 España