Senior MCU Firmware Engineer — Keyboard/Sensor & Always-On/Low-Power Domains

Seeking an experienced Senior MCU Firmware Engineer to own both microcontroller firmware domains of our next-generation embedded writer platform: the bare-metal firmware for a high-rate sensor-scanning keyboard subsystem — the hard-real-time heart of the device — and the always-on, low-power companion domain that remains active while the main applications processor is suspended. The selected candidate will design and implement microsecond-accurate sensor scanning, event timestamping, mechanical actuator control, and sensor calibration on a dedicated microcontroller, and will develop firmware for a low-power companion processor core driving an always-on status display, wake-trigger detection, battery monitoring, and system wake/sleep orchestration. Work is expected to phase — keyboard subsystem bring-up first, always-on domain second — but ownership of both domains is permanent and the full scope of each applies. This role requires strong hard-real-time firmware discipline, mixed-signal hardware fluency, strong low-power design instincts, comfort across a heterogeneous multi-core system, and the ability to prove determinism and power behavior with instrumentation, not argument.

•    Design and implement timer-triggered, DMA-driven analog sensor scanning across a large sensor array, with microsecond-accurate event timestamping.

•    Implement full simultaneous multi-input event capture and encoding for downstream transmission.

•    Design and implement a CRC-framed serial slave protocol for communicating scanned events and configuration to the main applications processor.

•    Design and implement multi-zone mechanical actuator drive (PWM-based, with soft-start/stagger sequencing) for haptic or force-feedback output.

•    Design and implement a sensor-to-actuator calibration system: baseline capture, per-position profiles, and safe masking during calibration/adjustment, validated on a bench test rig.

•    Provide firmware direction for a follow-on hardware revision, including any new sensing front-end technology under evaluation.

•    Develop firmware for a low-power companion processor core that must run continuously from on-chip low-latency memory through the main processor's suspend state.

•    Drive an always-on low-power display, including continuous low-rate refresh signaling.

•    Implement a digital microphone front-end pipeline for wake-trigger/voice-activity detection.

•    Implement battery/fuel-gauge polling and expose state to the rest of the system.

•    Design and implement wake/sleep orchestration logic in coordination with the platform firmware team, including transition timing and shared-resource ownership between processor cores.

•    Implement inter-processor messaging between the low-power domain and the main applications processor.

•    Own resource-partitioning decisions (memory, peripherals, interrupts) for the always-on domain in coordination with platform engineering.

•    Collaborate closely with electrical engineering on sensor/actuator circuit behavior and with platform engineering across both firmware domains.

•    Build and use bench validation tooling (oscilloscope/logic-analyzer driven) to demonstrate and document real-time determinism, and validate low-power behavior against a system-level power budget.

•    Participate in design and code review with particular attention to timing correctness, mechanical safety, power-state correctness, and wake-latency behavior.

•    Utilize modern AI-assisted development tools to accelerate development and test authoring, while applying independent engineering judgment and verification rather than trusting generated output at face value.

•    Support the product from early hardware bring-up through production release.

•    Bachelor's Degree in Electrical Engineering, Computer Engineering, or related field (or equivalent experience).

•    5+ years of professional bare-metal and/or RTOS-based microcontroller firmware development.

•    Mastery of microcontroller ADC, DMA, and timer peripherals for high-rate, precisely-timed data acquisition.

•    Demonstrated hard-real-time firmware discipline, with the ability to prove determinism using bench instrumentation (oscilloscope, logic analyzer) rather than analysis alone.

•    Mixed-signal hardware comfort: analog sensor interfacing and motor/actuator driver circuits.

•    Experience designing serial communication protocols (framing, CRC/checksums) between a microcontroller and a host processor.

•    Experience with heterogeneous multi-core SoC firmware, including coexistence and coordination between a main applications processor core and a low-power companion core.

•    Experience with inter-processor communication mechanisms in a heterogeneous SoC.

•    Strong low-power design instincts: sleep/retention states, current-budget-driven design trade-offs, wake-latency optimization.

•    Experience with at least one embedded RTOS (e.g., ThreadX, FreeRTOS, Zephyr, or similar).

•    Demonstrated, hands-on effectiveness with AI-assisted software engineering tools (agentic coding assistants, AI-based code review), with clear judgment about when to trust generated output and when it requires independent verification.

•    Excellent troubleshooting and debugging skills at the hardware/firmware boundary.

•    Experience using Git for version control and standard issue-tracking tools for project/task management.

•    Experience with keyboard, HID, or other high-rate sensor-scanning consumer/pro hardware.

•    Motor control or haptic actuator drive experience.

•    Experience with magnetic (Hall-effect) or other non-contact position-sensing technologies.

•    Prior experience specifically with a commercial applications-processor family that includes an integrated low-power companion core.

•    Basic audio/DSP experience (voice-activity detection, simple digital filtering).

•    Experience with always-on/low-power display technologies.

•    Prior RTOS product experience that transfers well to an always-on, resource-constrained environment.

•    Experience working in Agile development environments.

•    AI-Assisted Software Development

•    Bare-Metal / RTOS Microcontroller Firmware

•    ADC / DMA / Timer Peripheral Programming

•    Hard Real-Time System Design

•    Mixed-Signal Hardware Interfacing

•    Serial Protocol Design (CRC/Framing)

•    Motor/Actuator Control

•    Heterogeneous Multi-Core SoC Firmware

•    Low-Power / Always-On System Design

•    Inter-Processor Communication

•    Power-State & Wake/Sleep Orchestration

•    Basic Audio/DSP Front-End Processing

•    Bench Instrumentation & Validation

•    Git

•    Debugging & Troubleshooting