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Embedded Systems & IoT Product Development Engineer | STM32 • ESP32 • Nordic • Silicon Labs • PCB Design I help startups and companies transform ideas into production-ready embedded products. With 8+ years of experience in embedded systems, firmware development, PCB design, wireless connectivity, and product commercialization, I provide complete end-to-end engineering support—from concept and architecture to prototypes, testing, and manufacturing. My expertise spans industrial automation, IoT devices, wireless sensor networks, battery-powered systems, smart metering, wearable electronics, RF products, and custom embedded hardware. What I Deliver: • Embedded firmware development (Bare Metal, FreeRTOS, Zephyr) • Custom PCB design (Altium Designer, KiCad) • Hardware architecture and schematic design • Prototype bring-up, debugging, and validation • Low-power and battery-operated device optimization • Manufacturing-ready design packages (Gerbers, BOM, Assembly Files) • Design for Manufacturing (DFM) and Design for Test (DFT) • Technical documentation and production support Core Technologies: • STM32 (F0/F1/F4/F7/H7/U5/L0/L4/L5) • ESP32 (ESP-IDF, Arduino) • Nordic nRF52 Series • Silicon Labs EFR32 Series • RP2040 / Raspberry Pi • NXP and Microchip MCUs Wireless & Connectivity: • BLE / Bluetooth Low Energy • Wi-Fi • LoRa / LoRaWAN • Wi-SUN FAN • Zigbee • Thread / Matter • Cellular (LTE-M, NB-IoT, GSM) • RS-485 / Modbus • CAN / CAN-FD • Ethernet / TCP-IP • USB Applications & Sensors: • Environmental Monitoring • Industrial Automation • Smart Metering • Wearable Electronics • GPS Tracking • Energy Monitoring • Medical & Bio-Sensing Devices • Motor Control • Data Acquisition Systems Development Tools: • STM32CubeIDE • VS Code • Keil MDK • IAR Embedded Workbench • MPLAB X • Altium Designer • KiCad • LTspice • Git Whether you need a new product designed from scratch, firmware development for existing hardware, PCB design, debugging, or manufacturing support, I can help bring your project from concept to a reliable, market-ready product. Let's discuss your project and turn your idea into a working product.

I help companies debug, stabilize, and ship embedded products on STM32, ESP32, nRF52, EFR32, NXP KL17, JieLi, HDSC, and other ARM / RISC-V platforms. Typical problems I solve: • STM32 hard faults, crashes, boot issues • Custom board bring-up and peripheral integration • BLE / LoRa / MQTT connectivity issues • RS485 / Modbus communication instability • Low-power optimization for battery-operated devices • OTA reliability issues • Porting firmware to new boards, MCUs, or RTOS platforms • Turning prototypes into production-ready firmware I have 15+ years of embedded development experience across industrial communication systems, low-power IoT devices, wireless products, and mass-production consumer electronics. My background includes product lines with more than 10M devices shipped. Core platforms and technologies: • STM32 / ESP32 / nRF52 / EFR32/ NXP KL17 / JieLi • FreeRTOS / Zephyr / Arduino / PlatformIO • BLE / LoRa / NB-IoT / 4G / Cat.1 • RS485 / Modbus / UART / SPI / I2C • AWS IoT / MQTT / OTA • Battery-powered and ultra-low-power systems Selected experience: • STM32H7 controller platform with dual-core architecture, LVGL UI, RS485 communication, and ESP32-S3 connectivity co-processor • Ultra-low-power fault indicator for utility networks with multi-year battery life and LoRa communication • BLE thermal printer platform focused on wireless stability, motor control, print control, and production reliability Why clients work with me: • Strong debugging and root-cause analysis • Real production and manufacturing support experience • System-level architecture thinking • Clear communication and practical decisions • Reliable long-term collaboration Available for: • Firmware debugging and stabilization • Custom board bring-up • New feature development • RTOS-based firmware architecture • Wireless and industrial communication projects • Long-term embedded support Based in China (UTC+8), with flexible overlap for US / EU / AU teams. Typical response time: within 4 hours. Currently available for new debugging, bring-up, and embedded firmware support projects.

👋 Hello, I am YanXia Xu. Embedded Systems Engineer with nearly 30 years of experience in industrial automation and embedded firmware development. Specialized in MCU firmware, RTOS-based systems, industrial communication protocols, and embedded Linux platforms. Extensive experience supporting Japanese enterprise projects and long-term industrial product maintenance. Strong background in debugging, hardware-software integration, and reliable embedded system design.

I’m Simon, Heading the IoT Systems architecture at Maxlinktek (US), supported with my own high-performance R&D team in China. [Verified Profile Summary by Upwork AI System Engine]: “ An emerging IoT solution architect specializing in hardware and software integration, focusing on scalable IoT ecosystems. Demonstrated expertise in PCBA design, cloud infrastructure cost estimation, and embedded systems that facilitate seamless transitions from prototype to mass production [1] [2] [3]. Skilled in systems architecture, BOM optimization, and regulatory compliance, applying these capabilities to enhance design for manufacturing and production efficiency. Proven track record of delivering functional IoT products while minimizing costs and maximizing performance. Generated by Uma, Upwork’s Mindful AI, from completed jobs ” Skills: ● Systems/Product architecture. ● PCBA design (Altium/KiCad) ● Linux Kernel/APP development(C/C++) ● STM8/STM32/ESP32/CH59x BLE/Other MCUs development(C/C++) ● PHP Laravel + Swoole(server backend) ● VUE UI(HTML5/Javascript) ● Android/iOS APP development(Flutter/Electron) ● DFM (Design for Manufacturing): Optimization for high-yield assembly and die-casting to minimize defects. ● Mass Production (MP) Management: Experienced in overseeing the lifecycle from EVT/DVT/PVT to full-scale production. ● BOM Optimization: Strategic sourcing and component selection for supply chain resilience and cost-efficiency. ● Regulatory Compliance: Pre-scan and verification for international standards (UL, CE, FCC, IP67/68). I bridge the gap between US-standard strategic leadership and direct Shenzhen factory-floor execution.With 15+ years in Linux development & maintenance and 8+ years in professional PCBA engineering, I specialize in building production-ready IoT ecosystems — from the first circuit trace to global mass production. This setup allows me to provide US-standard communication and project management, combined with unmatched cost-efficiency and R&D speed through my dedicated team in China. FROM PROTOTYPE TO MASS PRODUCTION 🚀 WE BUILD SCALABLE IOT ECOSYSTEMS — NOT JUST DEMOS. Most IoT projects fail after the prototype stage. We bridge the gap between a "bench-top demo" and a global product launch.. 💡 WHY PARTNER WITH US? ● 30%-75% Hardware Cost Reduction: We replace bloated Android setups with high-performance Native ARM Linux. This achieves fluid UI/UX with lower hardware requirements and bedrock system stability. ● 20%-40% BOM Optimization: Leveraging deep Pearl River Delta supply chain expertise, we proactively suggest reliable chip alternatives to maximize your profit margins and secure components against global shortages. ● Zero-Gap Delivery: We perform deep on-site debugging and automated firmware flashing in China. You receive fully functional, validated hardware units—not bare, untested boards. 📦 PROVEN TRACK RECORD Due to strict NDA obligations with enterprise clients, only a selected portion of our portfolio is showcased below: ● LG DUOBO Coffee Machine: End-to-end integration (PCBA, Firmware, App). ● Nscreen32: World’s first LVGL-certified development board. ● Ntablet: Highly successful open-source hardware tablet framework. 🤝 WHO WE WORK WITH We partner with serious IoT startups and enterprise teams who view their hardware as a long-term venture. If you want to build a real, scalable product—not just a bench-top demo—we design for mass production from day one. 👉 Send an invite with a short description of your project, and I will suggest a high-level system architecture for your review.

I am a professional embedded software engineer with more than 10 years of experience. My current areas of expertise are IoT Applications & Embedded Systems Design, including embedded hardware/software. My Skills: - Know about MCU: Nordic, Silicon Labs, AVR, PIC,ESP32, etc. - Have experience in programming languages such as C/C++, - Solid knowledge of standard interfaces such as I2C, SPI, UART, and CAN. - Have experience using debugging tools such as Segger Jlink, CAN bus analyzer, Logic analyzer,RF analyzer. - IoT devices with wireless connectivity such as LTE, CAT-M1, NB-IoT, BLE, WIFI, NFC - Good experience in Battery Management Systems based on BQ products from TI. - Have experience using Alitium designer,Kicad - Know about medical Regulations and Directives such as EN 300 328,RoHS & REACH，EN 62368-1，EN 55032, EN 55035 etc. The development platform : - Keil .stm32cube, Micochip studio - On semiconductor IDE, Simplicity studio, - esp32-idf, Arduino - nrf connect sdk What I can do for you: (1 ) Electronic components selection,Schematic , PCBA design, output production files (2) Help you to review schematic , pcb files, and test hardware (3) quickly assist in making pcba samples, functional verification and abnormal problem analysis (4) Embedded software development from 0 to 1. (5) Help you to add new function or module to your embedded software system (6) Help you to review code ,test , fix bug in softeware (7) Based on the prototype of your needs, convert it into an actual embedded system design My advantage: （1） The processing and manufacturing efficiency in China is very high, and the cost of components is very low. If you want to do circuit modification and verification, I can use China's JLC and Taobao to quickly make PCBA. （2）I'm a full-stack developer capable of tackling both software and hardware challenges. This allows me to consider software design feasibility and convenience from a hardware design perspective, and vice versa.

I’m a Full-Stack Embedded Engineer specializing in MCU-based hardware and firmware design. From circuit schematics and PCB layout to firmware development, debugging, and production support — I deliver reliable, manufacturable embedded systems. ⚙️ What I Do 🔹 Embedded Hardware Design MCU-based circuit design (STM32, ESP32, Arduino, etc.) PCB layout for compact, power-efficient, and production-ready boards Power supply design, analog/digital signal routing, EMC/EMI consideration Prototype validation and debugging with oscilloscopes, logic analyzers 🔹 Embedded Firmware Development Bare-metal and RTOS firmware (FreeRTOS, ESP-IDF, STM32 HAL, Arduino) Communication interfaces: UART, I2C, SPI, CAN, BLE, Wi-Fi Sensor and actuator integration (ADC/DAC, PWM, GPIO, I/O expansion) Bootloader, OTA update, and low-power optimization 🔹 System Integration & Debugging Hardware-software co-design and joint debugging Interface communication validation and timing optimization Peripheral driver tuning and performance profiling 🔹 Production & Manufacturing Support DFM/DFA optimization for stable mass production BOM cost-down and alternative component sourcing Coordination with PCB and assembly vendors Prototype-to-production transition and testing support 🎓 Background Master’s degree in Electrical Engineering 5+ years of hands-on experience with MCU-based embedded systems Projects across IoT devices, industrial controllers, consumer electronics, and medical prototypes 🚀 What You Get ✅ Custom schematics + PCB layout for MCU systems ✅ Firmware development + hardware integration ✅ Prototype debugging and functional testing ✅ DFM optimization + production coordination ✅ Full documentation and support to manufacturing Whether you need a custom MCU board, firmware integration, or help turning your prototype into a manufacturable product, I’ll make sure your system runs efficiently, reliably, and ready for production. 💬 Let’s discuss your project and make it real!