Overview

Tonal is looking for a Senior Power Electronics Firmware Engineer to develop the firmware for our motor drive and power systems. That drive generates up to 250 pounds of digital weight, so its firmware defines how Tonal feels to every member. You’ll contribute at every stage, from concept, prototyping, and bring-up through validation and high-volume production.

You’ll join the Firmware team in our Hardware department, working closely with electrical, mechanical, and software engineers. Together, you’ll tackle challenges that span motor control, power conversion, thermal limits, and member safety. Our team offers a rare chance to shape the core technology of a new fitness category.

What You Will Do

Develop and improve motor control and power management firmware that makes Tonal’s digital weight feel smooth and responsive

Add and maintain protection features, such as overcurrent and overtemperature handling, that keep members safe

Bring up and debug new boards in the lab with the electrical team

Test and tune motor performance, and help build the tools and automated tests that validate each release

Support manufacturing test and calibration, and help investigate issues from the field

Work with software, mechanical, and product teams to turn member feedback into firmware improvements

Take part in design and code reviews, and help improve how the team builds and ships firmware

Who You Are

5+ years of embedded firmware development, including 3+ years focused on motor control or power electronics

Expert C development for real-time, resource-constrained systems; experience in C++ and Python is also valuable

Experience developing multithreaded firmware on an RTOS, including scheduling, synchronization, and interrupt handling for timing-critical tasks

Hands-on experience implementing FOC for PMSM/BLDC motors, including current-loop tuning and sensored or sensorless position estimation

Solid power electronics fundamentals: inverters, DC-DC converters, PWM techniques such as SVPWM, gate drivers, current and voltage sensing, and thermal behavior

Experience designing discrete-time control loops, filters, and observers, and modeling them in MATLAB/Simulink or Python

Experience with motor-control MCUs or DSPs (e.g., TI C2000, STM32, NXP) and communication protocols such as CAN, UART, SPI, and I2C

Experience with safety-critical systems, including protection, fault handling, and diagnostics for high-power hardware

Comfortable debugging at the hardware/firmware boundary with oscilloscopes, current and differential probes, power analyzers, and dynamometers

Creative problem solver who isn’t afraid to push boundaries and think differently, with high attention to detail

Great oral and written communication skills

Team player with high integrity and self-awareness, open to feedback and constantly striving to improve

Extra Credit

Experience with functional or appliance safety standards, such as IEC 60730 (Class B software), IEC 60335, IEC 61508, or ISO 26262

Experience managing regenerative energy in motor drives, such as braking resistor control and DC bus regulation

Experience with digitally controlled power conversion, such as PFC or DC-DC stages

Experience with unit testing, software- and hardware-in-the-loop (SIL/HIL) testing, Git, and CI tools such as Jenkins

Experience with EMC/EMI and safety compliance testing for motor drives

Experience with bootloaders and secure over-the-air firmware updates

Experience shipping high-volume consumer hardware

At Tonal, we believe that the unique and varied lived experiences of our teammates contribute to our overall strength. We don’t just appreciate differences, we celebrate them, and we always seek people that represent a wide variety of backgrounds. We’re dedicated to adding new perspectives to the team and designing employee experiences that contribute to your growth as much as you do to ours. If your experience aligns with what we’re looking for (even if you don’t check every single box), send us your application. We would love to hear from you!