Principal Engineer – Embedded Firmware

Enphase Energy•Fremont, CA

About The Position

Enphase is looking for an experienced FW development Engineer to design, develop, and optimize the firmware stack for our proprietary narrow‑band Power Line Communication (PLC) modems. You will own features across the PHY/MAC interface and MAC layer, collaborate with cross‑functional teams to translate system requirements into reliable firmware, and drive performance improvements in real‑world conditions. This role is ideal for an engineer who thrives at the intersection of embedded systems, communications stacks, and system integration.

Requirements

Bachelors or an advanced degree in Electrical Engineering, Computer Engineering, Computer Science or a related field
15+ years of experience in a similar job function
Strong proficiency in embedded C/C++ for microcontrollers (e.g., ARM Cortex‑M).
Experience developing firmware in bare‑metal environments and with RTOS architectures (interrupts, scheduling, DMA, low‑latency and memory-constrained design).
Hands-on experience with communication stacks (wired or wireless), including MAC‑layer concepts (queueing, access control, retries, timing, performance metrics).
Solid understanding of throughput, latency, reliability trade‑offs and how MAC‑layer algorithms influence real‑world system performance.
Strong HW/SW integration and debug skills using logic analyzers, oscilloscopes, protocol analyzers, and embedded debugging tools.
Demonstrated data‑driven problem‑solving, experiment design, and metrics-based performance evaluation.
Excellent written and verbal communication with strong documentation discipline.

Nice To Haves

Experience with narrow‑band PLC ecosystems such as G3‑PLC, PRIME, or IEEE 1901.2; understanding of channel conditions (noise, impedance variation, notching).
Familiarity with PHY/MAC interfaces and system‑level concepts (FSK/PSK/QAM/OFDM basics, link quality metrics) sufficient to interpret traces and collaborate with algorithm developers.
Scripting/analysis tools (Python, MATLAB) for log parsing, metrics tracking, and test automation.
Experience building/maintaining communication testbeds and/or channel emulation.
Exposure to security and reliability topics (secure boot, OTA update, watchdog/fault handling)

Responsibilities

Design, implement, and optimize firmware for narrow‑band PLC modems to ensure robust, high‑reliability communication across diverse operating conditions.
Develop firmware in both bare‑metal and RTOS environments, optimizing timing, memory, and processor efficiency.
Collaborate with hardware engineers, system architects, signal‑processing/algorithm teams, and application‑layer firmware developers to translate system requirements into production‑quality implementations.
Analyze and optimize MAC‑layer behavior, including throughput, latency, retry logic, reliability, and application-specific performance metrics.
Document designs, interfaces, and decisions to support knowledge sharing and maintain comprehensive project records.
Support system bring‑up and integration, troubleshoot hardware–software interactions, and provide technical support throughout development, validation, and product introduction.
Contribute to software quality through unit tests, integration tests, code reviews, and continuous improvement of tools and processes.