Principal Firmware Engineer

It's fun to work in a company where people truly BELIEVE in what they're doing!

We're committed to bringing passion and customer focus to the business.

If you like wild growth and working with happy, enthusiastic over-achievers, you'll enjoy your career with us!

Employment Type:

Full-time, Existing vacancy

Location:

San-Jose (On-Site)

At Lumentum, we’re building the tech behind the world’s fastest networks and most advanced systems. Our optical and photonic solutions power everything from AI and cloud computing to data centers, telecom, and advanced manufacturing.

We’re a global team of innovators working where light meets technology, solving big challenges that keep the world connected and moving forward. If shaping the future of connectivity excites you, you’ll fit right in.

Lumentum is seeking a Principal Firmware Engineer to lead architecture, design, and development of embedded firmware for advanced optical and photonic systems. In this role, you will drive technical direction across firmware platforms, partner closely with hardware, systems, and manufacturing teams, and deliver robust, high-quality firmware that meets performance, reliability, and compliance requirements for high-volume products.

• Own firmware architecture and technical roadmap for one or more embedded platforms supporting optical/laser/telecom or related high-reliability systems.
• Lead end-to-end firmware development: requirements → design → implementation → verification/validation → production release → sustaining.
• Develop firmware for MCU/MPU-based embedded systems (bare-metal and/or RTOS and/or embedded Linux), including board bring-up and low-level drivers.
• Define interfaces and protocols across firmware, hardware, FPGA, optics, and host software (e.g., I2C, SPI, UART, CAN, Ethernet; higher-layer protocols as applicable).
• Drive system reliability and quality: fault handling, diagnostics, telemetry, logging, upgrade mechanisms, and robust state-machine design.
• Lead design reviews, code reviews, and root-cause analysis for field issues; implement corrective and preventive actions.
• Collaborate cross-functionally with Systems, Hardware, Optical Engineering, Test, Reliability, Manufacturing, and Program Management to meet schedule and product goals.

BS in Electrical Engineering, Computer Engineering, Computer Science, or related field (MS preferred), or equivalent experience

• 10+ years of professional embedded firmware development experience, including ownership of shipped products.
• Expert proficiency in C/C++ for embedded systems, source code control (GIT), Segger IDE, Python, data analysis tools (i.e. JMP, R), Windows & Linux.
• Deep experience with RTOS development (e.g., FreeRTOS) and Bare-metal firmware (interrupts, bootloaders, HAL/LL drivers).
• Strong skills in board bring-up, debugging, and lab tools (JTAG/SWD, logic analyzer, oscilloscope, optical power meter, optical wavemeter).
• Solid understanding of hardware/firmware integration and digital interfaces (I2C/SPI/UART, GPIO, ADC/DAC, timers, DMA).
• Proven ability to lead technical decisions, drive architecture, and deliver across multi-disciplinary teams.
• Hands-on experience with optical components/modules calibration and control/PIDs including optical power control/APC loops, bias/current tuning, heater/thermal control, TEC/thermal control, optical signal monitoring, fault management and trend-based telemetry

• Direct experience developing firmware/software for optical transceiver modules and subsystems including bring-up, feature development, and production support.
• Strong familiarity with module management and host interfaces, including CMIS (Common Management Interface Specification); experience implementing, debugging, and validating management behaviors (state machines, paging/banked memory, diagnostics, alarms, and telemetry).
• Experience with optical components (i.e. lasers, MZ/IQ modulators, et cetera) control (i.e. PIDs), performance monitoring, and fault management.
• Understanding of manufacturing test flows and firmware…