As a recent graduate with a Bachelor's degree in Communication and Electronics Engineering, I am a passionate and highly motivated professional who has cultivated a strong foundation in the field of embedded systems. I am available to help you translate your ideas into professional 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 a highly skilled and detail-oriented PCB Design Engineer with over 3 years of experience in designing robust, efficient, and cost-effective printed circuit boards for various industries including consumer electronics, automotive, medical devices, and industrial automation. I specialize in converting complex circuit ideas into manufacturable and reliable PCB layouts. From schematic capture to final Gerber generation and fabrication-ready documentation, I ensure every step is precise and optimized for performance and manufacturability. 🔹My Expertise Includes: * PCB Design (2 to 16+ Layers) * Schematic Capture & Hardware Architecture * Embedded Hardware Design (STM32, ESP32, Nordic nRF, AVR, PIC) * Analog, Digital & Mixed-Signal Circuit Design * High-Speed PCB Design (USB, Ethernet, HDMI, DDR, PCIe) * RF PCB Design & Impedance Controlled Routing * Power Supply Design (Buck, Boost, LDO, Battery Management) * AC-DC & DC-DC Power Electronics * IoT Device Development * Sensor Interface Design * Industrial Control Electronics * Signal Integrity & Power Integrity * EMI/EMC Optimization * Thermal Management * High Current PCB Design * Differential Pair Routing * Controlled Impedance Design * Design for Manufacturing (DFM) * Design for Assembly (DFA) * Component Selection & Lifecycle Management * Prototype Development & Manufacturing Support 🔹PCB Design Services *Electronic Product Development *Circuit Design & Schematic Capture *PCB Layout & Routing *Hardware Design Review *Existing PCB Modification *Reverse Engineering *PCB Migration Between CAD Tools *Cost Optimization & BOM Engineering *Manufacturing Documentation *Prototype Validation Support 🔹Tools I Use: * Altium Designer * KiCad * Eagle * OrCAD / Cadence Allegro * EasyEDA * LTspice / PSpice / Multisim (for simulation) * AutoDesk Fusion 360 (for 3D enclosure fit checks) 🔹Deliverables You Can Expect: * Complete schematic and PCB layout files * BOM (Bill of Materials) * Gerber, drill, and pick-and-place files * 3D PCB renders * Assembly drawings and fabrication documentation * Technical support during prototype and production phases 🔹Industries *Industrial Automation *Consumer Electronics *IoT Products *Medical Electronics *Automotive Electronics *Smart Home Devices *Wearable Electronics *Power Electronics *Robotics *Communication Systems 🔹Why Choose Me? ✅ 100% custom and tailored designs ✅ Fast turnaround and clear communication ✅ Focus on reliability, quality, and cost optimization ✅ NDA-friendly and IP protection guaranteed Whether you're developing a new electronic product, improving an existing design, or preparing hardware for manufacturing, I can help transform your concept into a reliable, high-quality, production-ready PCB solution.

📌Embedded Systems Engineer with an industry experience of 5+ years in IoT and smart home automation. With a major in Mechatronics Engineering, I can design and develop your ideas to final product. I have an extensive experience in embedded software, firmware design, development and testing. Microcontrollers and Controllers: ✅ ESP32 (Espressif IDF and Arduino) ✅ AVR (Atmega8, Atmega16/32, Atmega328) ✅ Arduino ✅ Raspberry Pi ✅ NVIDIA Jetson Modules ✅ FPGA Spartan 6 Peripherals: ⚡ Sensors (Temperature, Current, Accelerometer etc.) ⚡ Actuators (Servo Motor, Stepper Motor, DC Gear Motor, Solenoid etc.) ⚡ Battery (Li-On, Li-Po, BMS etc.) ⚡ Displays (LCD, OLED etc.) Programming Languages: ⭐ C ⭐ C++ ⭐ Python Skills: ✨ Algorithm Development ✨ Problem Solving ✨ Program Logic ✨ OOP ✨ Data Structures Communication Interfaces: ▶️ Wi-Fi ▶️ UDP ▶️ TCP ▶️ UART ▶️ SPI ▶️ I2C ▶️ NFC Other than that, I have done multiple projects like IoT smart lock device, smart cooler project, person tracking system, smart switch etc. 📌

P R O F E S S I O N A L S U M M A R Y Results-driven Electronics Engineer with 14+ years of experience in Embedded Systems, Internet of Things (IOT) and High-Speed PCB Design. Proven expertise in end-to-end product development, from concept to mass production, with a strong focus on reliability, integrity, efficiency, and security. Adept at Agile workflows, crossfunctional collaboration, and managing engineering teams. Electronic System Design : Designed and developed advanced electronic systems for cash-handling machines, including power, sensors and data distribution and processing boards, leveraging STM32 microcontrollers, iMX8 MPUs, Raspberry Pi Compute Module CM4. Customized single board computers and carrier boards are designed with iMX8M and CM4 using DDR3L, HDMI, PCIE Gen 3, USB 3.0, CAN, Ethernet etc. Altium Designer is used for PCB designing. Hyperlynx SI & PI suits are used for signal integrity and power integirty of pcb boards. Efficient pcb stackups are designed for high speed and mixed signal boards. Power Distribution & Safety : Engineered efficient, reliable, and safe DC power distribution boards for various products, ensuring compliance with industry standards IPC-2221 and IPC-2152. EMI Mitigation & Signal Integrity : Implemented EMI noise suppression techniques using optimized PCB stack-ups and advanced filtering methods. Hardware Testing & Debugging : Conducted rigorous hardware testing and debugging to ensure optimal performance, reliability and functional compliance using test jigs, power loads, multimeters, oscilloscopes and logic analyzers. DFM, DFT & DFA Analysis : Performed Design for Manufacturing (DFM), Design for Testability (DFT), and Design for Assembly (DFA) analysis to streamline mass production. Version Control & Collaboration : Managed version control in hardware design using Git and Altium 365, ensuring efficient collaboration with team and design traceability. Firmware Development & Debugging : Developed and maintained secured firmware across the entire product line including secure OTA, STLink and JTAG are used for in-depth debugging and code optimization. Version control using Git and bitbucket for code management and maintenance. STM32Cube IDE is used as development framework environment. Secure Boot & Encryption : Implemented secure booting and encryption in firmware using STM32 Encryption SDK, integrating hardware encryption chips for enhanced security. AES is used for hashing and RSA for enhanced encryption. Procurement & Component Sourcing : Led component sourcing and procurement efforts for next-generation hardware products, ensuring supply chain efficiency and cost-effectiveness. Remote OTA Updates & Custom Bootloaders : Developed remote over-the-air (OTA) update mechanisms and custom bootloaders to enhance device maintainability and security. Custom Communication Protocols: Engineered proprietary communication protocols using Protocol Buffers and JSON for nextgeneration product integration and scalability. Agile Development & Project Management : Experienced in Agile workflows, utilizing Jira for tracking daily and biweekly tasks across multiple concurrent projects.

(Complete Embedded Hardware & Firmware Product Developer) I am an Electrical Engineer specializing in Firmware Programming, Embedded Systems, and PCB Development with hands on experience delivering real world hardware and automation solutions for industrial, IoT, defense, and consumer electronics applications. I am proficient in a wide range of microcontrollers and embedded platforms including STM32, ESP32, PIC, AVR, and Arduino. Hands on experience delivering 25+ real world products for defense systems, industrial automation, IoT devices, consumer electronics, motor control systems, and embedded hardware platforms. I can transform your idea into a complete working product by handling firmware development, embedded systems design, PCB layout, prototyping, debugging, testing, and production ready validation. I provide complete product development services including: ✔️ Firmware Development ✔️ Firmware Programming ✔️ Embedded Systems Design ✔️ PCB Design & PCB Development ✔️ FPGA Development ✔️ Hardware Prototyping ✔️ Industrial Automation ✔️ IoT Product Development ➤ 𝗙𝗶𝗿𝗺𝘄𝗮𝗿𝗲 𝗣𝗿𝗼𝗴𝗿𝗮𝗺𝗺𝗶𝗻𝗴 & 𝗘𝗺𝗯𝗲𝗱𝗱𝗲𝗱 𝗦𝘆𝘀𝘁𝗲𝗺𝘀 • Embedded Systems Development • Firmware Programming in Embedded C C++ • STM32 Firmware Development • ESP32 Firmware Programming • PIC, AVR & Arduino Firmware • Bare-Metal & RTOS Firmware Development • IoT Firmware Development • Wireless Embedded Systems • Embedded Linux Integration • UART, SPI, I2C, CAN, RS232, RS485 Communication • Bluetooth, BLE, Wi-Fi & LoRa Systems • Real-Time Embedded Systems • Sensor Integration & Control Systems ➤ 𝗣𝗖𝗕 𝗗𝗲𝘀𝗶𝗴𝗻 & 𝗘𝗹𝗲𝗰𝘁𝗿𝗼𝗻𝗶𝗰𝘀 𝗛𝗮𝗿𝗱𝘄𝗮𝗿𝗲 • PCB Design & PCB Development • High-Speed PCB Layout • Multilayer PCB Design • Altium Designer PCB Design • KiCad PCB Design • EasyEDA PCB Development • Analog PCB Design • Digital PCB Design • Power Electronics PCB • Embedded Hardware Design • Schematic Design & PCB Routing • Signal Integrity & EMI EMC Optimization • Motor Driver & Power Supply Circuits • Manufacturing-Ready PCB Design • Prototype PCB Development ➤ 𝗟𝗮𝗯𝗩𝗜𝗘𝗪 & 𝗧𝗲𝘀𝘁 𝗔𝘂𝘁𝗼𝗺𝗮𝘁𝗶𝗼𝗻 • LabVIEW GUI Development • Data Acquisition Systems • Test & Measurement Automation • Instrument Control Systems • Embedded Hardware Integration • Real-Time Monitoring Systems • Logging, Visualization & Analysis Tools ➤ 𝗦𝗶𝗺𝘂𝗹𝗮𝘁𝗶𝗼𝗻, 𝗧𝗲𝘀𝘁𝗶𝗻𝗴 & 𝗩𝗮𝗹𝗶𝗱𝗮𝘁𝗶𝗼𝗻 • MATLAB, LTspice & PSpice Simulation • Hardware Testing & Debugging • Firmware Debugging • PCB Testing & Validation • Signal Integrity Analysis • Engineering Validation Testing • Prototype Bring Up & Optimization • Performance Optimization Let’s connect and build your product professionally. Regards, Arslan

I'm an Embedded Firmware Engineer specializing in STM32 and ESP32 development, from bare-metal and FreeRTOS systems to embedded Linux. I work primarily in Embedded C/C++ and Rust, and I focus on reliable, low-level firmware for microcontroller-based products. Recent work that shows what I can do: - Rewrote an ESP32-C3 (RISC-V) second-stage bootloader in Rust (no-std, 32 KB IRAM) with Secure Boot V2 (ECDSA P-256), XTS-AES flash encryption, eFuse anti-rollback, and dual-slot OTA with automatic rollback, validated end-to-end in QEMU. - Wrote a FreeRTOS port from scratch for a PicoRV32 RISC-V softcore on an FPGA: custom IRQ entry, full context save/restore, and tick ISR, fit into 14 KB of BRAM with preemption verified on hardware. - Built a full-stack 18650 battery state-of-charge and state-of-health estimator on ESP32-S3 with on-device ML inference (under 1 ms, under 75 KB models) feeding a live dashboard. Core strengths: - STM32 / ESP32 firmware, bare-metal and RTOS (FreeRTOS) - Board bring-up and debugging (JTAG/SWD, logic analyzer, oscilloscope) - Drivers and protocols: UART, SPI, I2C, CAN, RS-485; OTA, persistent storage, fault handling - Embedded Linux: device tree, cross-compilation, userspace and kernel drivers (Raspberry Pi, Orange Pi) - FPGA / RTL (Verilog, VHDL) and MCU-FPGA co-design - Rust no-std firmware and RISC-V bring-up I prioritize clean architecture, predictable behavior, and clear communication throughout a project.

I run ML models on $5 microcontrollers — entirely offline, no cloud required. Most firmware engineers can write clean embedded C. Few can take a trained neural network, compress it 4x through INT8 quantization, and deploy it on a Cortex-M4 with 50ms latency and 12mW power draw. That's what I do. I've shipped MCU-based systems across industrial, automotive, and IoT domains for 30 years — from bare-metal bring-up to FreeRTOS task architecture. Recently I've been closing the gap between ML research and production hardware: PyTorch → ONNX → TFLite Micro, with CMSIS-NN acceleration and static memory allocation for deterministic real-time behavior. What I deliver: - On-device AI/ML inference on STM32, ARM Cortex-M (TFLite Micro, CMSIS-NN) - FreeRTOS firmware with sensor fusion, SPI/I2C/UART, low-power design - Full pipeline from model training to flashed firmware - Production-ready code from prototype to mass production If you're building something that needs to be smart, small, and always-on — let's talk.

I design and develop production-ready firmware for connected and embedded systems, with a strong focus on reliability, performance, and long-term maintainability. My work spans the full development lifecycle, including system architecture, firmware design and implementation, hardware bring-up, optimization, and deployment support for production environments. I primarily work in C and C++ for ARM Cortex-M, ESP32, and NRF52 platforms. Both bare-metal and RTOS-based approaches are used, especially FreeRTOS, to build deterministic and efficient embedded systems. This includes designing multitasking architectures, handling interrupts, and implementing low-level peripheral control for real-time applications. Strong experience with embedded communication protocols such as SPI, I2C, UART, CAN, BLE, and WiFi, along with development of custom drivers for sensors and external hardware. The focus is on stable integration and efficient operation in resource-constrained embedded environments. On the IoT side, I build firmware for secure and reliable connectivity between devices and cloud platforms. This includes MQTT-based telemetry systems, REST API integration, OTA update support, and low-power optimization techniques such as sleep modes, deep sleep, and duty cycling for battery-powered devices. I also handle hardware bring-up and system-level debugging to support early-stage development and integration between firmware and hardware. Close collaboration with hardware teams ensures smooth integration between PCB design and firmware behavior. In addition, I have experience in embedded AI and edge computing, including deploying TinyML models on microcontrollers. I work with startups, hardware teams, and product companies, helping take embedded products from early prototypes to production deployment, as well as supporting existing systems through debugging, optimization, and firmware evolution.

I design, debug and industrialise embedded products: firmware, PCB, BLE, Wi-Fi, UWB and RTLS. Top Rated Plus, 100% Job Success, 4,400+ Upwork hours and 20+ years of professional electronics experience. 🏆 𝗣𝗥𝗢𝗩𝗘𝗡 𝗨𝗣𝗪𝗢𝗥𝗞 𝗥𝗘𝗖𝗢𝗥𝗗 ✔️​Top Rated Plus ✔️​100% Job Success ✔️​4.9/5 client rating ✔️​55 completed jobs ✔️​4,400+ hours ✔️​Long-term and repeat clients ✔️​Paid technical consultations available My ratings, completed contracts and client feedback are publicly visible below. Many clients first hired me for a specific firmware, PCB or debugging problem and later trusted me with larger developments or long-term engineering support. 🎯 𝗪𝗛𝗘𝗡 𝗖𝗟𝗜𝗘𝗡𝗧𝗦 𝗛𝗜𝗥𝗘 𝗠𝗘 ✔️​Develop a new embedded or connected product ✔️​Turn a prototype into a reliable, manufacturable device ✔️​Recover a delayed or technically troubled project ✔️​Debug intermittent hardware, firmware or wireless failures ✔️​Refactor difficult-to-maintain embedded code ✔️​Define firmware or system architecture ✔️​Review schematics, PCB layouts and RF designs ✔️​Integrate BLE, Wi-Fi, UWB or RTLS ✔️​Reduce power consumption ✔️​Prepare a product for certification or production ✔️​Add senior technical leadership to an existing team 🧠 𝗖𝗢𝗥𝗘 𝗘𝗫𝗣𝗘𝗥𝗧𝗜𝗦𝗘 𝗘𝗺𝗯𝗲𝗱𝗱𝗲𝗱 𝗳𝗶𝗿𝗺𝘄𝗮𝗿𝗲 Embedded C/C++, Zephyr, FreeRTOS, bare metal, firmware architecture, HAL, drivers, middleware, state machines, bootloaders, secure boot, OTA, diagnostics, static analysis, testing, MISRA-C, BARR-C, Doxygen and legacy-code refactoring. 𝗛𝗮𝗿𝗱𝘄𝗮𝗿𝗲, 𝗣𝗖𝗕 𝗮𝗻𝗱 𝗥𝗙 System architecture, component selection, schematics, multilayer PCB design, high-density layouts, low-power electronics, RF layout, antenna integration, power integrity, hardware bring-up, DFM, DFT and production preparation. 𝗪𝗶𝗿𝗲𝗹𝗲𝘀𝘀 Bluetooth Low Energy, Wi-Fi/Wi-Fi 6, UWB, RTLS, Matter, Thread, MQTT, TCP/IP, BSD sockets, UART, SPI, I2C, CAN, USB, tags, anchors, sensors and gateways. 𝗣𝗹𝗮𝘁𝗳𝗼𝗿𝗺𝘀 Nordic nRF52/nRF53/nRF54/nRF70, Qorvo UWB, STM32, NXP LPC/i.MX, ESP32 and ARM Cortex-M systems. 🤝 𝗢𝗙𝗙𝗜𝗖𝗜𝗔𝗟 𝗣𝗔𝗥𝗧𝗡𝗘𝗥𝗦 I am the founder and technical director of A Blue Thing In The Cloud S.L.U., an official Nordic Semiconductor Design Partner and Qorvo UWB Partner. I remain directly involved in architecture, critical design decisions, debugging and code review. For larger projects, I can add the permanent ABTC engineering team while retaining technical leadership. 🔧 𝗛𝗢𝗪 𝗜 𝗪𝗢𝗥𝗞 1️⃣Understand the product, constraints and commercial objective. 2️⃣Identify technical and project risks. ​​3️⃣​Review available hardware, firmware and documentation. 4️⃣​Define architecture, milestones and acceptance criteria. 5️⃣Implement and validate incrementally. ​6️⃣​Document the design and important decisions. 7️⃣Prepare the product for testing, certification and manufacturing. I value clear communication and realistic commitments. If an approach is unsafe, unnecessarily expensive or unlikely to work, I will explain that before consuming your budget. 📞 𝗣𝗔𝗜𝗗 𝗧𝗘𝗖𝗛𝗡𝗜𝗖𝗔𝗟 𝗖𝗢𝗡𝗦𝗨𝗟𝗧𝗔𝗧𝗜𝗢𝗡𝗦 A complete development is not always the right first step. You can book an Upwork consultation for: ✔️​Product feasibility and architecture ✔️​Firmware, PCB or prototype review ✔️​BLE, Wi-Fi, UWB or RTLS decisions ✔️​Debugging and project recovery ✔️​Technical-debt assessment ✔️​Certification and industrialisation planning ✔️​Scope and risk review before a larger project You may send requirements, schematics, logs, photographs or code extracts beforehand. The meeting focuses on technical decisions, risks and next actions—not a sales presentation. 🚀 𝗡𝗘𝗫𝗧 𝗦𝗧𝗘𝗣 Send me a short description of the product, its current stage, the main technical challenge and any deadline, certification or manufacturing constraint. For focused senior advice, book a paid consultation. For a defined development, send an invitation through Upwork. When technology becomes art.