Mixed Signals Electronics Engineer in Harwell

Infleqtion is a global quantum technology company solving the world’s most challenging problems. The company harnesses quantum mechanics to build and integrate quantum computers, sensors, and networks. From fundamental physics to leading‑edge commercial products, Infleqtion enables "quantum everywhere" through our ecosystem of devices and platforms.

LOCATION: Infleqtion has offices in the USA, United Kingdom, and Australia. This is a full‑time position split between our Kidlington, Oxford office and the National Quantum Computing Centre, Harwell. Work from home is permitted up to 2 days per week based on business needs and manager approval.

JOB SUMMARY: We are looking for a Mixed Signals Electronics Engineer with a passion for working with a multi‑disciplinary team to bring state‑of‑the‑art quantum technologies outside the laboratory and into the real world. You will use your skills to contribute to the design, verification, and implementation of electronic systems and subsystems for Infleqtion’s quantum products. This role requires strong skills and relevant experience with mixed‑signal and analogue electronics, supporting the advancements of our innovative solutions.

JOB RESPONSIBILITIES:

• Design and develop mixed signal electronics systems that interface digital and analogue components effectively
• Translate functional requirements into PCBA implementation
• Perform modeling, simulation, and analytical calculations to ensure system stability and performance
• Conduct PCB design and layout, focusing on signal integrity and optimal routing techniques
• Generate manufacturing files and auxiliary documentation for PCB fabrication
• Build prototypes and PCBAs, modify and fix errors when required
• Develop and execute testing protocols to validate design performance against specifications
• Collaborate closely with other engineering disciplines to integrate mixed‑signal solutions into larger systems
• Support supplier identification and engagement for component sourcing

REQUIREMENTS:

• Bachelor’s degree or substantive experience in electrical engineering, electrical and computer engineering, or related fields
• Excellent understanding of both analogue and digital circuit principles, with a focus on mixed‑signal design
• Experience full PCB design lifecycle from taking functional specifications to generating manufacturing data
• Hands‑on experience with PCB design tools (e.g., Altium) and simulation software (e.g., SPICE)
• Demonstrated ability to troubleshoot and resolve complex electronics issues
• Experience utilizing laboratory equipment for testing and validation, such as oscilloscopes, spectrum analysers, and network analysers
• Experience building prototypes and loading components on PCBs by hand
• Good communication skills, with the ability to collaborate within cross‑functional teams

DESIRABLE SKILLS AND KNOWLEDGE:

• Experience with digital signal processing (DSP) techniques
• Knowledge of RF design and integration related to mixed‑signal systems
• Familiarity with product life cycle management, from initial design through production and support
• Experience with microcontroller programming or FPGA development
• Familiarity with digital communication protocols like SPI, I2C, UART, Ethernet

EQUAL OPPORTUNITY: Regardless of your interest in the quantum industry, you can take pride in the fact that Infleqtion is building an ecosystem of quantum technologies and commercial products, driving the industry towards the future. Studies reveal that while men apply for jobs when they meet an average of 60% of the requirements, women and other groups tend to apply only when they meet all the criteria. If you believe you have the potential but don’t meet every single point in our job advertisement, please don’t hesitate to contact us! We would love to chat with you and see how you could bring great value to our team. Our goal is to find exceptional individuals who can enrich our team culture, actively contribute, and have a genuine passion for their work. Here you have freedom to embrace your whole self: who you love, your gender identity and expression, skin colour, age, appearance, disability, neurodiversity, DNA, military/veteran status, citizenship, and other factors that make up who you are. Your uniqueness is valued, welcomed, and appreciated here. We are dedicated to providing a positive workplace and base all employment decisions on your qualifications, performance, merits, as well as business needs. We are proud to be an Equal Employment Opportunity Employer.

BENEFITS:

• Competitive salary
• Unlimited PTO
• Generous company 10% pension contribution regardless of employee contribution
• Cycle to work scheme
• Tax efficient technology schemes
• Incentive Stock Option Plan
• BUPA Private Healthcare Insurance once probationary period is successfully completed