Job Description

Flux Computing designs and manufactures optical processors to train and run inference on large AI models. Join us in London to be part of a highly motivated and skilled team that thrives on delivering impact and innovation at speed.

The Role

We're searching for a Senior/Staff/Analog Design Engineer with a strong focus on CMOS analogue design to lead the design, validation and productisation of ultra?high?speed (> 10 GHz) transimpedance amplifiers that sit at the electrical-optical front end of our OTPU. The role demands deep expertise in low?noise, wide?bandwidth analog circuit design, simulation and measurement. The ideal candidate will pair a solid grounding in semiconductor physics with a passion for building reliable, production?worthy TIAs that unlock new levels of AI?hardware performance.

Responsibilities

Design and develop high?speed CMOS TIAs - from schematic through post?layout verification, lab bring?up and production test - meeting stringent bandwidth, input?referred?noise and linearity targets for our optical links. Work hand?in?hand with opto?electronic and packaging teams to co?design the photodiode, package, and PCB interconnect that surround the TIA, ensuring seamless system integration. Analyse circuit performance, identify bottlenecks (e.g. excess input capacitance, stability, power), and implement innovative solutions such as inductive peaking, active feedback, or process?corner tuning to optimise speed, noise and power. Mentor junior engineers, run in?depth design and layout reviews, and champion best?practice methodologies for high?frequency, low?noise analog design. Track and bring into the team the latest advances in TIA architectures, CMOS processes, RF?EDA flows and test techniques to keep Flux at the cutting edge.

Skills & Experience

7 + years of industry experience in CMOS integrated?circuit design with a primary focus on high?speed, low?noise analog front ends (TIA, LNA, or similar). Mastery of analog/RF EDA flows: schematic capture, SPICE and S?parameter simulation, layout and parasitic extraction, and post?silicon characterisation. Proven track record of meeting sub?pA/ Hz input?referred noise, multi?10?GHz bandwidth and tight power budgets in a shipping product. Bachelor's degree in Electrical Engineering (or related); Master's / PhD a plus. Strong problem?solving skills, especially in feedback stability, transmission?line effects, package modelling and de?embedding. Excellent collaboration and communication abilities for effective cross?disciplinary teamwork. Demonstrated success in fast?paced environments where innovation and rapid iteration are paramount. A portfolio of personal or open?source projects - or published papers/patents - that highlights creative analog or RF design thinking.

Compensation & Benefits

Competitive salary and stock options, you're not just part of the journey, you will own a piece of it. Work from our HQ in King's Cross, right in the middle of London's buzzing AI scene. Live within 45 minutes of the office? Perfect. Live within 20 minutes? We'll add an extra

24,000 a year

to your salary. We offer visa sponsorship and full relocation support (UK and abroad), through a dedicated third-party provider who are on hand to make your move to London as seamless as possible. Full BUPA healthcare and dental cover, medical history disregarded. High-spec tech for everyone - M4 Macs as standard, M4 Pros for Engineers. Sony noise-cancelling headphones and ergonomic setups to keep you comfortable and focused. Personal company card to spend on tools that help you do your job - like ChatGPT Pro or anything else that boosts your workflow. Healthy, chef-cooked dinners in the office every night, with something for every diet and tastebud. Monthly off-site team socials. 25 days of paid holiday, plus all the UK bank holidays. Access to our in-house 3D printer for personal or work projects. Cycle2work scheme. Need a caffeine fix? We've got you covered with a tab at our favourite local coffee shop. We offer a pension plan and salary sacrifice options.

We're building fast and that includes our benefits. More exciting additions are coming soon for the Flux crew.

If you are passionate about pushing the boundaries of what's possible in AI and thrive in a high-energy, fast-paced environment, we want to hear from you. Apply now to join Flux and be a key player in shaping the future of computing.