Job Overview

Are you an innovative hardware leader who thrives on driving cutting-edge electronics from initial concept to production? Do you prefer the challenge of owning complex, low-voltage control systems and guiding cross-functional teams through technical hurdles over routine, single-phase component tweaking? Mainspring Energy is looking for a highly autonomous, intellectually curious, and influential Senior Electrical Engineer, Electronics Design to join our core Electrical Engineering organization. Unlike traditional electrical design roles confined to narrow subsystems or isolated schematic capture, this is a high-impact engineering position where you will take end-to-end ownership and act as the technical lead for the critical electrical hardware and PCBA designs that power our revolutionary Linear Generator. Working alongside a world-class team of multidisciplinary engineers, you will have the execution autonomy to design advanced low-voltage (< 60V) systems, spearhead complex hardware validation and technical reviews, and directly shape the future of our power generation control architecture.

Responsibilities

Mainspring's Linear Generator is unlike any other generator technology on the market. The Linear Generator relies on innovative electrical power and control hardware systems to achieve its best-in-class efficiency while meeting the world's strictest emissions requirements. These electrical hardware systems are designed by a talented team of electrical engineers that own hardware design from initial concept through test and manufacturing. We have a high impact opportunity for an electronics engineer to shape the future of the Linear Generator's electrical control hardware systems. As a member of the team, you will:

• Low-Voltage Hardware Design: Design low-voltage (< 60V) electrical systems and PCBAs that enable core functions and expand the capability of the Linear Generator
• Bring-Up & Validation: Own the full bring-up, validation, and qualification of your custom electrical hardware designs
• Technical Reviews: Lead cross-functional design reviews to present concepts, align requirements, and secure approvals
• Complex Diagnostics: Debug and troubleshoot complex hardware issues that arise across field deployments, test labs, and the production floor
• Design for Reliability: Partner closely with reliability engineers to analyze hardware performance and continuously increase system robustness
• Manufacturing Collaboration: Work directly with our New Product Introduction (NPI) team and external suppliers to optimize designs for manufacturability (DFM) and testability (DFT)
• Cross-Domain Integration: Interface with high-voltage hardware teams and define requirements for cabling and embedded firmware support
• Team Growth: Learn complex design concepts and mentor peers while collaborating with a world-class engineering team

Qualifications

You have...

• 5+ years of experience with a Bachelor's degree, or 4+ years of experience with a Master's degree, in Electrical Engineering or a related field
• Proven hands-on experience designing, troubleshooting, and realizing low-voltage electrical hardware (e.g., DC/DC converters, relays, e-fuses, and MOSFETs)
• Proficiency with PCBA schematic capture and PCB design tools (Altium strongly preferred)
• Strong fundamentals in analog/mixed-signal design, including operational amplifiers, ADCs, and hardware filtering (anti-aliasing, bandpass, etc.)
• Experience performing component derating analysis, worst-case tolerance stack-ups, and Design Failure Mode and Effects Analysis (DFMEA)
• Demonstrated ability to drive projects forward from initial requirements through production
• A "collaborate-first" mindset with strong communication skills across diverse technical teams and personalities

Preferred Qualifications

• Experience in the full hardware development life cycle of PCBA's and electrical assemblies, from requirements development to manufacturing support
• Familiarity with hardware reliability and environmental validation testing (e.g., HALT, thermal chamber testing, Hipot, vibration)
• Experience working in a startup or rapid product development environment
• Familiarity with project management and documentation tools (e.g., Jira, Confluence)
• Basic programming or scripting experience (Python, C, or C++) specifically for automating lab bench tests or debugging hardware

$130,050 - $153,000 a year

This position is onsite at our Menlo Park HQ. The salary will be adjusted to reflect local market conditions based on employee location as well as the experience of the employee. Along with the base salary, Mainspring offers pre-IPO stock options + benefits.

Does your experience not meet all of our posted requirements? Studies have shown that some people are less likely to apply to positions unless they meet every listed requirement. At Mainspring, we are committed to building a diverse, inclusive, flexible, and collaborative environment, so if you want to help us transition the world to clean and affordable electricity, and don't meet all posted requirements for a particular role, we'd still love to hear from you. Mainspring can sometimes be flexible enough to shift responsibilities for the right person, or otherwise identify open or upcoming roles that may better fit your professional background.