Proper Voltage

• Own the operational supplier relationships across multiple commodity categories, including electrical, cables, harnesses, packaging, and consumables. • Run the day-to-day RFQ, quote, and PO process, from technical package through quote normalization, supplier selection, and order placement. • Manage long lead time component visibility, tracking, and expediting against build schedules. • Drive supplier cadence: weekly status, monthly business reviews where appropriate, scorecards, and corrective action when performance drifts. • Onboard new suppliers brought in through Director-led strategic sourcing, including qualification logistics, NDA execution, and commercial setup. • Partner with engineering during NPI to source components against evolving specs, manage long lead and allocation-risk items, and ensure material readiness for prototype and pilot builds. • Own and maintain the CTB tracker across active builds. Reconcile on-hand, on-order, and in-transit quantities against build schedules and phase requirements. • Maintain clean PO records on quantities, pricing, delivery commitments, and receipt status.

• Own end-to-end commodity strategy for electrical components • Build and qualify a production-ready supplier base for components currently on single-source risk, allocation constraint, or prototype-only relationships • Lead all supplier and distributor negotiations for electrical commodities: pricing, payment terms, lead times, allocation commitments, and supply agreements • Partner with engineering during NPI to source electrical components ahead of build events, manage long-lead and allocation-risk items, and ensure material readiness

• Own PCB layout from concept through release using Altium Designer • Design multi-layer boards (4–12+ layers) for: Battery Management Systems (BMS) DC-DC converters and power stages High-current distribution • Optimize for: High-current paths & low impedance Thermal performance EMI/EMC compliance • Define stack-ups and collaborate directly with fabrication and assembly partners • Build and maintain component libraries and design rules in Altium • Support bring-up, debugging, and rapid iteration cycles

We review general interest applications on a rolling basis and reach out when an opportunity aligns with your background and ambitions. Even if we don’t have the perfect role open today, we regularly review these submissions and will reach out if there’s a future fit. Thanks for taking the time to introduce yourself, we’re excited to learn more about you!

• Work on hard engineering problems in battery technology for robotics, data centers, and defense • Collaborate on intelligent battery systems

Job Overview We are in search of a Senior Embedded Software Engineer to join our Concepts Group—a fast-paced, small team responsible for taking product concepts from leadership and rapidly building minimum viable implementations to determine feasibility and inform go/no-go decisions for full product development. This is not a traditional firmware role. You will work on a new problem every few weeks to months, standing up just enough firmware to prove whether an idea works: getting a new cell chemistry on a BMS, prototyping a novel protection scheme, spinning up a communication stack on unfamiliar hardware, or validating a control algorithm on a bench rig. The emphasis is on speed, resourcefulness, and sound engineering judgment—knowing what corners can be cut in a prototype and what cannot. The ideal candidate is someone who thrives on variety, can go from a blank STM32 project to a working proof-of-concept faster than most engineers think is possible, and has enough depth in BMS and power electronics firmware to know which shortcuts are safe and which will give you misleading results. You will work closely with engineering leadership to scope concepts, define success criteria, and deliver clear recommendations on whether a path forward exists. What You’ll Do • Receive product concepts and technical challenges from engineering management and rapidly translate them into scoped, time-boxed firmware prototyping efforts. • Build minimum viable firmware implementations on STM32 platforms (Cortex-M33/M4) to validate feasibility of new BMS architectures, cell chemistries, protection strategies, and communication topologies. • Stand up functional firmware quickly on new or unfamiliar hardware—bring up peripherals, verify signal chains, and get to meaningful data collection in days, not weeks. • Prototype and evaluate fuel gauging approaches (Kalman filters, coulomb counting, hybrid methods) across different battery chemistries to assess viability before committing to production implementation. • Rapidly implement and test cell balancing strategies, protection algorithms, and fault detection logic to evaluate trade-offs in accuracy, complexity, and cost. • Develop quick-turn communication interfaces (CAN, UART, SPI, I2C, Ethernet) to integrate prototype BMS modules with existing systems or test rigs. • Interface with analog front ends, isolated amplifiers, current sense circuits, and DAQ hardware to validate measurement architectures on prototype builds. • Produce concise, actionable technical assessments—documenting what works, what doesn’t, key risks, and a recommended path forward for the product development team. • Collaborate with hardware engineers to quickly evaluate new component choices, alternate topologies, and cost-reduction opportunities at the firmware level. • Build throwaway tooling, test scripts, and data logging utilities as needed to support rapid evaluation cycles. • Maintain a library of reusable firmware building blocks (drivers, protocol stacks, algorithms) that accelerate future concept evaluations. • Exercise a high degree of autonomy, take ownership, and contribute as a key individual to project milestones and objectives. • Ability to either work in person at our Carlsbad, CA office or travel there as needed with a demonstrated track record of highly efficient, collaborative remote work. Required Qualifications • B.S., M.S., or Ph.D. in Computer Engineering, Electrical Engineering, Computer Science, or related field. • 6+ years of experience developing embedded firmware, with a demonstrated ability to move fast and deliver working prototypes under tight timelines. • Deep proficiency with ARM Cortex-M microcontrollers (STM32 strongly preferred), including the ability to bring up new hardware from scratch with minimal documentation or support. • Broad peripheral experience: ADC, DMA, timers, SPI, I2C, UART, CAN—comfortable picking up unfamiliar peripherals and getting them running quickly. • Strong experience with RTOS-based firmware (FreeRTOS, Zephyr, or equivalent) and the judgment to know when bare-metal is the faster path for a prototype. • Proficiency in C for embedded systems; working knowledge of C++ and/or Rust for embedded applications. • Solid understanding of analog signal chains, ADC calibration, filtering, and precision measurement—enough to evaluate whether a prototype’s data is trustworthy. • Hands-on experience with CAN bus implementation and at least passing familiarity with multiple communication protocols. • Strong understanding of power electronics fundamentals as they relate to firmware control (gate drive timing, protection sequencing, current limiting). • Proficiency with embedded debugging tools (JTAG/SWD, logic analyzers, oscilloscopes, protocol analyzers). • Excellent engineering judgment: the ability to distinguish between prototype-acceptable compromises and shortcuts that invalidate results. • Strong written and verbal communication skills—must be able to distill prototype findings into clear go/no-go recommendations for leadership. • Self-directed and comfortable operating with ambiguous requirements and short timelines. Preferred Qualifications • Direct experience with battery management system firmware, including cell balancing, fuel gauging, and pack protection. • Experience with multiple battery chemistries (lithium-ion, sodium-ion, lithium-titanate, LiFePO4) and an understanding of how chemistry differences affect firmware requirements. • Exposure to functional safety concepts (IEC 61508, ISO 26262) and safety-critical firmware design patterns. • Knowledge of compliance standards for battery systems (UL 1973, UL 9540, IEC 62619). • Experience with digital control loops for power converter regulation. • Track record of working in a skunkworks, R&D, or rapid prototyping environment. Prior Experience With • Kalman filters or similar estimation algorithms applied to battery state estimation. • CPLD/FPGA integration for hardware-level protection and fast fault response. • Isolated amplifier and measurement circuit interfacing (AMC1301, AMC1311, or similar). • High-voltage BMS architectures (100V+) with multi-chemistry support. • Emulation and simulation frameworks (Renode, QEMU) for accelerating early firmware development. • Using Python for rapid data analysis, visualization, and test automation. • Bidirectional DC-DC converter control and associated firmware. Compensation & Benefits • Salary range: $165,000 – $200,000 depending on experience and qualifications. • Equity options as part of the compensation package. • Comprehensive healthcare benefits (medical, dental, vision). • Generous paid time off and paid holidays (PTO) policy. Ready to prove what’s possible before anyone else believes it? Let’s talk.

Job Overview We are looking for an Embedded Software Engineer who is passionate about writing firmware that runs on real hardware in safety-critical environments. In this role, you will develop and maintain firmware for our battery management systems running on STM32 microcontrollers, implementing core BMS functions including cell monitoring, protection algorithms, communication protocols, and sensor interfaces. You’ll work closely with hardware and senior firmware engineers to bring up new boards, integrate analog front ends, and ship production-quality firmware across multiple battery chemistries. This is a hands-on individual contributor role within a fast-moving, multi-disciplinary engineering team. What You’ll Do • Develop and maintain BMS firmware on STM32 platforms (Cortex-M33/M4) in C, targeting safety-critical battery applications across sodium-ion, lithium-titanate, and lithium-ion chemistries. • Implement and test peripheral drivers for ADC, SPI, I2C, UART, CAN, DMA, and timers as part of the BMS firmware platform. • Develop firmware for cell voltage and temperature monitoring, over/under-voltage and over-current protection, and thermal management. • Implement and tune passive cell balancing algorithms for multi-series pack configurations. • Integrate and validate analog front-end interfaces, including isolated amplifiers (AMC1301), current sense circuits, and voltage divider chains. • Develop CAN bus communication firmware for BMS-to-host data exchange, status reporting, and command interfaces. • Write, execute, and maintain unit tests and hardware-in-the-loop tests to validate firmware functionality and fault response. • Support board bring-up activities: verify power rails, validate peripheral communication, and debug hardware/firmware integration issues. • Collaborate with hardware engineers on schematic review and provide firmware-side input on signal routing, filtering, and component selection. • Contribute to firmware documentation including design descriptions, interface specifications, and test procedures. • Support safety compliance efforts by implementing firmware requirements derived from FMEA and fault tree analysis for UL 1973 certification. • Participate in code reviews and contribute to continuous improvement of firmware development practices. • Ability to either work in person at our Carlsbad, CA office or travel there as needed with a demonstrated track record of highly efficient, collaborative remote work. Required Qualifications • B.S. or M.S. in Computer Engineering, Electrical Engineering, Computer Science, or related field. • 3+ years of experience developing embedded firmware in C for ARM Cortex-M microcontrollers. • Hands-on experience with STM32 peripherals: ADC, SPI, I2C, UART, CAN, DMA, and GPIO. • Experience with RTOS-based firmware development (FreeRTOS, Zephyr, or equivalent). • Familiarity with embedded debugging tools and workflows (JTAG/SWD, logic analyzers, oscilloscopes). • Understanding of analog signal chains as they relate to firmware: ADC sampling, filtering, calibration, and noise management. • Experience with CAN bus communication protocols and message framing. • Proficiency with version control (Git) and structured development workflows. • Ability to read and interpret hardware schematics, datasheets, and reference manuals. • Effective communication skills across various levels of the organization. • Proven ability to multitask and thrive in a fast-paced startup environment, with minimal supervision. Preferred Qualifications • Experience with battery management system firmware or power electronics control. • Exposure to functional safety concepts and safety-critical firmware practices. • Knowledge of compliance standards for battery systems (UL 1973, UL 9540, IEC 62619). • Experience with digital filtering techniques (moving average, low-pass IIR, Kalman filters) applied to sensor data. • Familiarity with current sensing techniques, isolated measurement circuits, and precision ADC applications. Prior Experience With • C/C++ for embedded development. • Hardware-in-the-loop testing and emulation frameworks (Renode, QEMU). • CPLD or FPGA interfacing from a firmware perspective. • Using Python for scripting, log analysis, and test automation. • High-voltage systems (100V+) and associated safety practices. Compensation & Benefits • Salary range: $130,000 – $160,000 depending on experience and qualifications. • Equity options as part of the compensation package. • Comprehensive healthcare benefits (medical, dental, vision). • Generous paid time off and paid holidays (PTO) policy. Ready to write the firmware that powers the future of energy? Let’s talk.

Job Overview We are in search of a Senior Embedded Software Engineer to join our Concepts Group—a fast-paced, small team responsible for taking product concepts from leadership and rapidly building minimum viable implementations to determine feasibility and inform go/no-go decisions for full product development. This is not a traditional firmware role. You will work on a new problem every few weeks to months, standing up just enough firmware to prove whether an idea works: getting a new cell chemistry on a BMS, prototyping a novel protection scheme, spinning up a communication stack on unfamiliar hardware, or validating a control algorithm on a bench rig. The emphasis is on speed, resourcefulness, and sound engineering judgment—knowing what corners can be cut in a prototype and what cannot. The ideal candidate is someone who thrives on variety, can go from a blank STM32 project to a working proof-of-concept faster than most engineers think is possible, and has enough depth in BMS and power electronics firmware to know which shortcuts are safe and which will give you misleading results. You will work closely with engineering leadership to scope concepts, define success criteria, and deliver clear recommendations on whether a path forward exists. What You’ll Do • Receive product concepts and technical challenges from engineering management and rapidly translate them into scoped, time-boxed firmware prototyping efforts. • Build minimum viable firmware implementations on STM32 platforms (Cortex-M33/M4) to validate feasibility of new BMS architectures, cell chemistries, protection strategies, and communication topologies. • Stand up functional firmware quickly on new or unfamiliar hardware—bring up peripherals, verify signal chains, and get to meaningful data collection in days, not weeks. • Prototype and evaluate fuel gauging approaches (Kalman filters, coulomb counting, hybrid methods) across different battery chemistries to assess viability before committing to production implementation. • Rapidly implement and test cell balancing strategies, protection algorithms, and fault detection logic to evaluate trade-offs in accuracy, complexity, and cost. • Develop quick-turn communication interfaces (CAN, UART, SPI, I2C, Ethernet) to integrate prototype BMS modules with existing systems or test rigs. • Interface with analog front ends, isolated amplifiers, current sense circuits, and DAQ hardware to validate measurement architectures on prototype builds. • Produce concise, actionable technical assessments—documenting what works, what doesn’t, key risks, and a recommended path forward for the product development team. • Collaborate with hardware engineers to quickly evaluate new component choices, alternate topologies, and cost-reduction opportunities at the firmware level. • Build throwaway tooling, test scripts, and data logging utilities as needed to support rapid evaluation cycles. • Maintain a library of reusable firmware building blocks (drivers, protocol stacks, algorithms) that accelerate future concept evaluations. • Exercise a high degree of autonomy, take ownership, and contribute as a key individual to project milestones and objectives. • Ability to either work in person at our Carlsbad, CA office or travel there as needed with a demonstrated track record of highly efficient, collaborative remote work. Required Qualifications • B.S., M.S., or Ph.D. in Computer Engineering, Electrical Engineering, Computer Science, or related field. • 6+ years of experience developing embedded firmware, with a demonstrated ability to move fast and deliver working prototypes under tight timelines. • Deep proficiency with ARM Cortex-M microcontrollers (STM32 strongly preferred), including the ability to bring up new hardware from scratch with minimal documentation or support. • Broad peripheral experience: ADC, DMA, timers, SPI, I2C, UART, CAN—comfortable picking up unfamiliar peripherals and getting them running quickly. • Strong experience with RTOS-based firmware (FreeRTOS, Zephyr, or equivalent) and the judgment to know when bare-metal is the faster path for a prototype. • Proficiency in C for embedded systems; working knowledge of C++ and/or Rust for embedded applications. • Solid understanding of analog signal chains, ADC calibration, filtering, and precision measurement—enough to evaluate whether a prototype’s data is trustworthy. • Hands-on experience with CAN bus implementation and at least passing familiarity with multiple communication protocols. • Strong understanding of power electronics fundamentals as they relate to firmware control (gate drive timing, protection sequencing, current limiting). • Proficiency with embedded debugging tools (JTAG/SWD, logic analyzers, oscilloscopes, protocol analyzers). • Excellent engineering judgment: the ability to distinguish between prototype-acceptable compromises and shortcuts that invalidate results. • Strong written and verbal communication skills—must be able to distill prototype findings into clear go/no-go recommendations for leadership. • Self-directed and comfortable operating with ambiguous requirements and short timelines. Preferred Qualifications • Direct experience with battery management system firmware, including cell balancing, fuel gauging, and pack protection. • Experience with multiple battery chemistries (lithium-ion, sodium-ion, lithium-titanate, LiFePO4) and an understanding of how chemistry differences affect firmware requirements. • Exposure to functional safety concepts (IEC 61508, ISO 26262) and safety-critical firmware design patterns. • Knowledge of compliance standards for battery systems (UL 1973, UL 9540, IEC 62619). • Experience with digital control loops for power converter regulation. • Track record of working in a skunkworks, R&D, or rapid prototyping environment. Prior Experience With • Kalman filters or similar estimation algorithms applied to battery state estimation. • CPLD/FPGA integration for hardware-level protection and fast fault response. • Isolated amplifier and measurement circuit interfacing (AMC1301, AMC1311, or similar). • High-voltage BMS architectures (100V+) with multi-chemistry support. • Emulation and simulation frameworks (Renode, QEMU) for accelerating early firmware development. • Using Python for rapid data analysis, visualization, and test automation. • Bidirectional DC-DC converter control and associated firmware. Compensation & Benefits • Salary range: $165,000 – $200,000 depending on experience and qualifications. • Equity options as part of the compensation package. • Comprehensive healthcare benefits (medical, dental, vision). • Generous paid time off and paid holidays (PTO) policy. Ready to prove what’s possible before anyone else believes it? Let’s talk.