Principal Electrical Engineer - PCB

About Radiant

Radiant is an El Segundo, CA-based startup building the world's first mass-produced, portable nuclear microreactors. The company's first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases.

Radiant's unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028.

About the Role

Radiant is seeking a Principal Electrical Engineer with deep expertise in PCB design to define and lead the electrical architecture for terrestrial reactor control systems, with a long-term path toward space reactor applications. You will serve as the foremost technical authority for custom hardware across the organization - setting design standards, driving architecture decisions, and owning the end-to-end development of high-reliability, low-noise printed circuit boards from requirements definition and schematic capture through layout, bring-up, validation, and field deployment.

This role emphasizes full-stack PCB development, including mixed-signal design, high-speed interfaces, power distribution, and signal integrity, while supporting data acquisition, signal conditioning, estimation, and real-time processing functions critical to reactor control. As a principal-level contributor, you will shape the technical roadmap for Radiant's hardware platform and mentor engineers across the electrical team.

Responsibilities & Duties:

* Own the design and development of multilayer PCBs for reactor control and instrumentation systems (terrestrial, with future space applications).

* Define and own the electrical architecture strategy for mixed-signal systems, including power distribution, analog front ends, and digital control interfaces.

* Design low-noise analog front-end circuits and ensure robust integration with ADC/DAC and digital subsystems.

* Perform schematic capture, component selection, and PCB layout with focus on signal integrity, power integrity, grounding, and EMI/EMC mitigation.

* Develop and review high-speed, high-precision layouts (e.g., sensor interfaces, data-acquisition paths, communication buses).

* Bring up, debug, and validate hardware, including board-level testing, instrumentation, and root-cause analysis.

* Create and execute hardware validation and qualification test plans for performance, reliability, and environmental conditions.

* Collaborate cross-functionally with firmware, FPGA, DSP, and responsible engineers to ensure seamless hardware/software integration.

* Provide technical leadership and mentorship to junior and senior electrical engineers; lead design reviews and own hardware risk identification and mitigation.

Required

Qualifications & Skills:

* Bachelor's degree in Electrical Engineering or a related field.

* 8+ years of experience designing custom PCBs, including multilayer and mixed-signal boards.

* Demonstrated experience setting electrical architecture direction and driving decisions across complex, multi-disciplinary programs.

* Strong experience with schematic capture and PCB layout tools (e.g., Altium, Cadence, or similar).

* Solid understanding of signal integrity, power integrity, grounding strategies, and EMI/EMC mitigation techniques.

* Experience with analog and mixed-signal design, including sensor interfaces, ADC/DAC integration, and low-noise design practices.

* Familiarity with high-speed interfaces (e.g., SPI, I2C, UART, Ethernet) and layout constraints.

* Hands-on experience with board bring-up, debugging, and lab instrumentation (oscilloscopes, spectrum analyzers, VNAs, etc.).

* Ability to work across disciplines and support system integration in a complex engineering environment.

Desired

Qualifications &…