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I’m building a compact, 4–6-layer mixed-signal board that will sit at the heart of a new sensor-interface product. The board must collect analog data, run it through an on-board DSP, and then push results out over Wi-Fi, Bluetooth, and a cellular link. To keep the unit fully portable, all power must be managed through an integrated battery management system, including charging, protection, and efficient rail generation for the analog, digital, and RF domains. Here’s what I need from you, start to finish: • Complete schematic capture with full part selection, paying special attention to RF front-ends, low-noise sensor inputs, the DSP section, and the battery management circuitry. • A 4–6 layer stack-up that cleanly separates noisy digital, sensitive ana...

I’m building a handheld device that lets me roll a ball across any flat surface and have it actively steer itself so the pen mounted inside draws in the exact direction I choose. An optical-flow sensor will read surface motion, my code will translate that into heading commands, and two small motors inside the ball will supply the corrective spin. The overall sketch is already under way, but I need a specialist who knows Arduino-style hardware and, more importantly, how to marry miniature motors with an ESP32-C module for precise directional control of the ball. Your main focus will be advising on the right motor format, driver circuitry, power budgeting, and the physical/electrical integration so the firmware can call simple functions like setHeading() or setVelocity(). I’m ...

I need a Class D audio amplifier with tone control Bass Treble designed for professional audio equipment. The amplifier should deliver a power output between 100W to 500W. Key Requirements: - Input Support: XLR and RCA - Power Output: 100W to 500W - Suitable for professional audio applications Ideal Skills and Experience: - Expertise in designing Class D amplifiers - Experience with professional audio equipment - Knowledge of XLR and RCA input integration - Proven track record in high-power audio amplifier projects Please provide portfolios and relevant experience.

我已从设备上安全拆下 7037IC 芯片，物理状态完好。现在希望在对芯片零损伤的前提下，一次性读取出其中的手机操作系统固件。为协助你完成工作，我可以提供： • 高分辨率引脚照片 • 电路连接信息 • 芯片实物寄送 首选方案是使用 JTAG 工具；若你建议配合 ISP 编程器、NAND Flash 编程器或其他专用设备，也请说明理由与流程。 交付要求 1. 读取并生成完整可验证的操作系统固件映像（BIN 或 HEX）。 2. 同步提交哈希值或其他完整性校验证明，确保数据无缺失、无篡改。 3. 附一份简要读取日志或说明文件，便于我后续分析。 4. 如在提取过程中顺带获得基带或引导固件，请仅在说明中备注，交付物仍以操作系统固件为准。 期待你分享过往使用 JTAG（或相关工具）成功提取芯片数据的案例，说明所用设备、步骤及为何对芯片安全。请在接手后于一个月内完成全部交付。 如果你擅长精确引脚定位、信号完整性处理、低电压读取等细节，欢迎提出你的方案——我会根据专业程度与成功率优先选择合作。

need a straightforward 2-bit counter designed entirely with discrete Bipolar Junction Transistor (BJT) logic. My priority is to keep the component count as low as practical while still delivering clean, glitch-free counting through the four binary states (00-01-10-11). • Use only BJTs – no FETs, ICs, or microcontrollers • Favor the fewest possible transistors and passives without compromising function • Standard 5 V logic levels are ideal, though I’m open to 3.3 V if that helps reduce parts Ultimately, the most important thing is that the design works practically on the breadboard—without issues and without noise.

We are Unikeyic, a global electronic components distributor, and we are looking for experienced technical writers for a long-term collaboration. If you have a background in electronics engineering and enjoy writing high-quality technical content, we'd love to hear from you. What You'll Do You will write original technical articles related to electronic components and circuit design, including topics such as: Semiconductor devices Passive components PCB design Embedded systems Power management Electronic component selection Industrial automation IoT applications Electronic engineering tutorials The article title, outline, target keywords, and writing requirements will all be provided by us. Requirements To be considered, please make sure you meet most of the following require...

I'm seeking an experienced RF circuit designer to develop an RF amplifier. The amplifier should operate in the high-frequency range of 3 GHz to 30 GHz, with a medium output power level between 1W and 10W. Ideal Skills and Experience: - Expertise in RF circuit design - Proficiency in working with high-frequency components - Experience with medium power RF amplifiers - Knowledge of stability and linearity in RF circuits - Familiarity with simulation tools (e.g., ADS, HFSS) Please provide relevant work samples and a brief project plan.

I’m developing a signal-processing module and need a purpose-built power inverter circuit to drive it reliably from a 12 V DC source. The job centres on circuit design; PCB work can follow later once the schematic is locked down. Here’s what I’m looking for: • A complete schematic for a high-efficiency DC-to-AC inverter that delivers clean, low-ripple rails suitable for sensitive analogue and mixed-signal stages. • Component selection with readily available parts and clear justification for each choice. • SPICE-level simulations (LTspice, PSpice or similar) showing expected efficiency, output wave-form quality and thermal performance under 25 W continuous load. • A brief design report summarising calculations, key assumptions and any trade-offs ...

我手头有一颗7037ic芯片，需要完整提取其中的固件，并在拿到固件后针对设备当前出现的问题做一次故障排除层面的分析。 工作内容分为两步： 1. 固件提取 • 使用合适的 ISP/JTAG 或其他可靠手段，安全读取 7037ic 内部全部固件。 • 提供原始 .bin 或 .hex 文件，并说明所用接口、引脚连接及工具版本，确保后续可复现。 2. 故障排除分析 • 对提取出的固件进行静态或动态分析，找出可能导致设备异常的代码段、配置或校验机制。 • 提交一份简明报告，列出发现的问题点、复现步骤与建议的修复思路。 我可以配合提供板卡照片、供电参数及已观测到的故障现象。希望你有芯片逆向、固件分析、硬件调试方面的实战经验，并能在沟通中说明具体方案与所需时间。

I need a Level 2 (240V) EV charger installed at my landed house in Kajang, Selangor. Requirements: - Professional installation - Ensure compliance with local electrical codes - Test the charger to confirm it's working properly Ideal Skills & Experience: - Licensed electrician - Experience with EV charger installations - Knowledge of local regulations

I need an experienced embedded hardware / PCB engineer to design a production-ready STM32-based main controller PCB for a therapeutic massage/spine bed system. This is a build-to-spec project. I already have a detailed engineering handoff package including system architecture, old PCB references, estimated current budget, pin maps, connector notes, BOM guidance, firmware handoff notes, layout requirements, and test plans. The freelancer’s main responsibility is hardware design and manufacturing outputs: schematic, PCB layout, Gerbers, BOM, assembly files, and firmware-ready hardware documentation. Firmware will be developed separately using AI/Codex/Claude from existing working ESP32 firmware. I will burn the firmware once the board is ready. The PCB must support first firmware flash...

I need a PCB hardware designer who already understands fuel-grade gas dispenser electronics and has hands-on experience designing intrinsically safe circuits. The job centres on the control system of the dispenser; the board you create must reliably manage flow-rate control while meeting the strict electrical safety demands of hazardous-area operation. Here’s what I expect from the engagement: • Develop a full schematic that integrates the pump’s sensors, valve drivers and my chosen microcontroller, then add a custom zener-barrier stage to limit energy into the hazardous zone. • Lay out a compact, production-ready PCB (Altium Designer or KiCad are both fine) observing creepage, clearance and thermal guidelines for ATEX/IECEx intrinsic-safety compliance. • P...

# FastForm Capacitive Sensor Electrode — PCB Design & Order Brief --- ## Overview I need a **very simple 2-layer PCB** designed and manufactured. Two variants, 5 boards each. **This board has no components, no traces, no schematic, and no routing.** It is four copper rectangles and three vias. Someone competent with KiCad should complete the layout in under an hour. **Important context so the design decisions make sense:** this is not a normal circuit board. It is a **capacitive sensor electrode** that will be immersed in wet concrete. The **solder mask is a functional dielectric layer**, not a cosmetic finish. Several instructions below will look unusual for a PCB — please follow them exactly rather than applying normal PCB conventions. --- ## Deliverables 1. **KiC...

Electrical teknisi Pemasangan intalasi listrik dan repair

I need help bringing a single-layer PCB back to life. At the moment it shows three clear problems: several components have failed, some traces are visibly damaged, and the board refuses to power up consistently. I can supply the original Gerber/layout files, but the schematic is no longer available, so part of the task will involve tracing the nets and inferring the missing circuit details. Your job is to: • Pin-point every faulty component and specify equivalent replacements • Locate and mend any open or shorted traces, or propose jumper fixes where copper is beyond repair • Restore a clean, stable power rail and verify correct voltage levels under load • Give me a concise repair log that includes measurements, photos of each fix, and final functional tests A ...

The square wave should have an equal mark-to-space ratio, a frequency equal to that of the resonant frequency of the metal bar estimated in Part 1, and an output voltage going from 0 volts to +15 volts. Show full working for calculating component values and draw the circuit diagram. Part 1 is measure the frequency response of one of the metal bars from the Electronics Lab. You will need to use the signal generator (function generator) and oscilloscope to do this. Plot the resulting frequency response across the range 100kHz to 200kHz, and state the resonant frequency of the metal bar.

I need a PCB layout design for a small general lighting application using standard LEDs. The PCB size should be less than 10x10 cm. Ideal skills and experience include: - Proficiency in PCB design software (e.g., Altium Designer, Eagle, or KiCAD) - Experience with LED circuit design - Knowledge of layout techniques for thermal management - Attention to detail and accuracy in design

I have a working concept for an E-Rickshaw diagnostic tool based on an ESP32 DevKit V1, and I now need a production-ready 2-layer PCB. All circuitry must operate from the vehicle’s 48 V line, stepped down via an LM2596. The board will drive an I2C OLED, measure battery voltage, and sense individual lines for the horn, headlight, indicators, brake light, and reverse buzzer. Two probes (A & B) are included for quick continuity tests. Good engineering practice is mandatory: reverse-polarity, fuse, TVS and general input protections must be designed-in. Preferred workflow • KiCad is my first choice; if you feel EasyEDA delivers clear advantages, let me know. • Layout decisions should favour ease of assembly over sheer compactness or extra thermal tricks. • Blueto...

I need a cable assembly made from our plans for a toilet flush sensor prototype. The assembly involves a combination of flat cable and pre-made cable that we will cut and extend. We have built a couple of basic units but need about a dozen made for field trials. Requirements: we can provide some of the materials - cutting and extending off the shelf IoT sensor cable - Speaker flat extension cables - will need water proofing Ideal Skills and Experience: - Experience with flat cable and general assembly - Proficiency in working with pre-made cables - Attention to detail and precision in cable cutting and extending - water proofing and protecting Looking for a skilled professional to ensure a reliable and functional assembly. Please provide relevant experience in your bids. this may be i...

I already have a KiCad v10.4 design exported to Gerber and will share the schematic, PNG layout images and an initial BOM. What I need now is a careful re-work so the board prints flawlessly on a Voltera V-One. Here is the scope in plain terms: • Import my existing Gerbers, then modify and optimise them for a 2" × 3" FR1 board. • Advise whether the plated holes should be drilled for 1.0 mm or 0.4 mm copper rivets and implement the correct drill table. • Provide full design assistance: refine component selection and placement, reroute traces for cleaner paths, and add or remove small features where that improves manufacturability or current handling. • Keep all components at least 0.4 in from each corner; the corner mounting holes themselves are n...

I am looking for an experienced Embedded Hardware Design Engineer to develop a custom production-ready WIFI Board for a proprietary embedded electronic product. The selected engineer will be responsible for reviewing the project requirements, designing the complete schematic, selecting suitable components, creating the WIFI Board layout, and preparing the design for manufacturing. Required Expertise - Embedded hardware design - Mixed-signal WIFI Board design - RF WIFI Board layout - Power supply design - Battery-powered embedded systems - Design for Manufacturing (DFM) - Design for Assembly (DFA) - Schematic capture and WIFI Board layout (KiCad or Altium preferred) Deliverables - Complete schematic - WIFI Board layout - Bill of Materials (BOM) - Gerber files - Manufacturing files - A...

Please note: Max payment for this is $140. Please do not bid and then negotiate higher price if this is not acceptable. I need a KiCad project that lays out a compact, dual-rail power supply capable of delivering up to 10 A per rail at a maximum of 70 V. The board will sit inside an audio amplifier chassis and will be fed by a toroidal transformer, so low noise and a clean ground scheme are critical. Core requirements • Dual CRC-filtered rails with the 0 V reference converging only at the final capacitor. • A single pair of screw terminals at the board edge for each secondary winding so wiring from the toroid stays short and tidy. • Support for a 5020-class diode bridge (through-hole) plus an alternate footprint that lets me mount the bridge directly to the chassis v...

We are looking for an experienced Power Electronics Engineer / PCB Design Engineer to design three high-power solar inverter systems from scratch: On-Grid (Grid-Tie) Inverter Off-Grid Inverter Hybrid Inverter Power rating: 30kW to 50kW — this is industrial-scale, three-phase equipment, not a residential 1-5kW unit. We need engineers who have specifically worked at this power level before. We will start with one inverter type first (to be confirmed after proposals), then move to the others upon successful completion. We have reference datasheets/manuals from existing market products (ASHAPOWER, TruePower, UTL, Waaree, etc.) that will be shared as benchmarks for specs and features. The design itself must be original/from scratch — not a copy of any existing product. Delive...

Title: Full-Stack Embedded Engineer: KiCad Flex-PCB Design & STM32 Firmware for Capacitive Sensing Array Project Objective: We are prototyping a wearable biomechanics system for a para-athlete runner to measure Vertical Impact Peak (VIP) and asymmetry. The hardware architecture utilizes a custom multi-channel capacitive force sensor array (copper pads separated by a cellular polyurethane/Poron dielectric) embedded in a shoe insole/cleat. We need a full-stack embedded systems engineer to design the custom Flexible PCB layout in KiCad and write the bare-metal C/C++ firmware for an STM32 microcontroller to process the sensor data. Key Deliverables & Scope: 1. KiCad Flex-PCB Layout: - Design a custom-shaped, ultra-thin Flexible PCB (Flex-PCB) insole footprint based on provided ...

A pin header on my small production PCB was accidentally soldered one pad off its intended footprint, so the connector now sits in the wrong position. The task is straightforward: cleanly remove the existing header, clear the through-holes without lifting pads or damaging traces, and solder a new (or the same, if salvaged intact) header perfectly aligned to the original footprint. Because this is essentially a solder-joint-related rework, I expect professional tools—hot-air rework station, fine-tip iron, quality flux, microscope inspection—to be used. Once the header is resoldered, please verify continuity on every pin, check for bridging, and confirm the board still powers up. Deliverable: • Returned, fully functional PCB with the pin header accurately seated and all jo...

Project Title Design & Development of Wide Input Isolated Dual Output DC-DC Flyback Converter (20V–160VDC Input | 12V/1A & 5V/0.5A Outputs) Project Overview We are looking for an experienced Power Electronics Engineer with proven expertise in isolated SMPS and flyback converter design to develop a compact, industrial-grade DC-DC converter module. The converter will operate from a 20VDC to 160VDC input and provide two fully regulated isolated outputs: 12V DC @ 1A 5V DC @ 0.5A The product will be used in industrial control systems, battery-powered equipment, and EV-related applications. The design must emphasize high reliability, stable operation over the complete input voltage range, thermal performance, electrical isolation, and manufacturability. Only freelancers with...

Project Title Electronic Speed Controller (ESC) & Flight Controller Hardware Design Engineer for Defence UAV Project Description We are looking for an experienced **Electronics/Embedded Systems Engineer** to design and develop an indigenous **Electronic Speed Controller (ESC)** and **Flight Controller** for our defence UAV platform. This is a long-term project with the possibility of continued collaboration on future UAV systems. # Scope of Work # Electronic Speed Controller (ESC) * Design BLDC ESC (60A–120A, scalable up to 200A) * Schematic design * PCB Layout (KiCad or Altium) * Component selection (MOSFETs, Gate Drivers, Current Sensors, Regulators) * Thermal management * EMI/EMC considerations * Gerber Files * Bill of Materials (BOM) * Manufacturing files * Prototype ...

I’m setting up a new mobile-phone venture and I want a seasoned PCB designer to join me at the ground floor. I will fund the hardware development; what I need from you is the end-to-end PCB engineering that turns our handset concept into a manufacturable reality. Scope of work • Architect and lay out a multilayer board that fits a slim smartphone form factor. • Integrate the core silicon (application processor, memory, RF front-end), battery interface and power-management circuitry, plus all critical sensor breakouts. • Optimise signal integrity, thermal behaviour and EMI/EMC so the design can clear FCC/CE without major rework. • Produce complete deliverables—schematics, layered Gerber/ODB++ files, annotated BOM, pick-and-place data and a brief DFM ...

I'm seeking an expert in firmware and hardware integration, specifically for radio communication. This project involves developing both firmware and the necessary hardware components. Key Requirement: - Custom Protocol: The firmware must support a custom communication protocol tailored to our specific needs. Ideal Skills and Experience: - Proficiency in radio communication systems - Experience with custom protocol development - Strong background in microcontrollers and circuit design - Knowledge of data acquisition and control systems is a plus Please share your relevant experience and approach to this project.

I need a clear, component-level wiring diagram that shows exactly how to build a compact rechargeable lamp. The diagram must be laid out as a classic wiring diagram (not a high-level schematic) so wire colours, connection points and conductor paths are unambiguous for a technician to follow. Components used to fit in a 100*100*20mm compartment Project context The lamp will run from an internal battery pack, drive a small cluster of LED lights, and recharge via a dedicated charging circuit. A capacitive touch sensor will act as the on/off. Everything should fit on a single board with any external leads clearly marked. Essential inclusions • Battery pack : to have 7-8hrs backup for the LED mentioned below • LED : 3 V, 33 mA LED filaments • Charging circuit (USB-C prefe...

Project Golden Eagle couples solar, a lithium-ion battery energy storage system and gas-fired reciprocating engines into one behind-the-meter plant that will offset our facility’s demand charges and provide resilient back-up power. The preliminary economic model is complete; what remains is a construction-ready electrical design that folds the three resources into a single, code-compliant package. The generation mix is fixed—solar arrays, BESS and gas engines—as confirmed in our internal feasibility study. I already have detailed equipment specifications, protection philosophies and utility interconnection requirements; these must be reflected verbatim in the drawings and calculations you prepare. Where gaps appear, NEC 2023, IEEE 1547 and local AHJ amendments should gui...

I need a complete PCB design built around the ESP32-C3 and five onboard power MOSFETs. The board will sit inside a medium-sized, handheld consumer-electronics enclosure and run from a regulated mains-derived supply, so careful attention to isolation, creepage, and thermal paths is essential. The circuit will drive five independent high-side or low-side loads (I can adapt to whichever topology is simpler on your end) while giving the ESP32-C3 solid Wi-Fi/BLE antenna performance. GPIO pin mapping, level-shifting, protection, and a clean 3 V3 rail must all be worked into the schematic. Please route with sensible trace widths, keep EMI in check, and leave me a little proto area for future tweaks if space permits. Deliverables • Schematic and well-annotated PCB layout • Gerber, ...

I am looking for an experienced PCB layout engineer to design and route a compact, dual-layer PCB for an IoT smart switch module. The design must fit inside a very restricted space (approximately 55mm x 45mm) to fit behind standard wall switchboards. Key aspects of the design: - Microcontroller: ESP32-WROOM-32 series (Wi-Fi + BLE). - Power: On-board AC-to-DC isolated converter (230V AC to 5V DC) and a 3.3V DC-DC buck converter. - Relays: 1x onboard relay switching AC mains load. - Inputs: Single-channel external switch sensing circuit. - Safety & Protection: Fuse and surge protection (MOV), with strict clearance/creepage rules (minimum 2.5mm spacing between high-voltage AC mains and low-voltage DC logic traces). - Tools: KiCad preferred. Deliverables: - Schematic review and optimizat...

Je souhaite concevoir puis réaliser un système d’irrigation intelligent, connecté en IoT, dédié aux cultures de céréales. L’objectif est de réguler l’apport en eau par irrigation de surface en fonction de données temps-réel recueillies par des capteurs d’humidité du sol et de température. Concrètement, il me faut : • l’architecture complète (choix du microcontrôleur – Arduino, ESP32 ou équivalent –, réseau LoRa/Wi-Fi, passerelle, cloud ou serveur local), • le schéma de câblage incluant électrovannes ou pompes pour l’irrigation de surface, • le code embarqué qui lit les capteur...

Hi I will share the details with the shortlisted candidates. Thanks