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Circuit Design is the process of designing electrical circuits to create a complete electronic system. A Circuit Designer is responsible for designing circuits, testing the board and components through simulations, troubleshooting any errors, and even prototyping the board by manufacturing a few before completing the entire circuit accurately. Through this intricate process, a Circuit Designer will be able to optimize the design with their expertise and creative talent to push out an efficient product.
Circuit Designers are knowledgeable engineers with a high level understanding of electronics engineering and components that can be used in a circuit. They also possess analytical skills as they must be able to calculate loads, power consumption and sophisticated circuit architecture that involves cause and effects to produce sound results. With extensive knowledge of hardware engineering, Circuit Designers are responsible for hardware selection, board sizing, and routing of signals.
Here's some projects that our expert Circuit Designer made real:
These projects use both beginner and advanced electrical engineering techniques that our expert Circuit Designers are capable of delivering. With creativity, knowledge in engineering disciplines and product optimization experience, our Circuit Designers create reliable and innovative solutions for our clients’ projects.
We invite you to post your project on Freelancer.com so you can experience what our group of expert Circuit Designers have to offer. With their strong background in electronics engineering and creative problem solving, our freelancers can create dependable and optimized circuits for your project.
From 41,255 reviews, clients rate our Circuit Designers 4.84 out of 5 stars.Circuit Design is the process of designing electrical circuits to create a complete electronic system. A Circuit Designer is responsible for designing circuits, testing the board and components through simulations, troubleshooting any errors, and even prototyping the board by manufacturing a few before completing the entire circuit accurately. Through this intricate process, a Circuit Designer will be able to optimize the design with their expertise and creative talent to push out an efficient product.
Circuit Designers are knowledgeable engineers with a high level understanding of electronics engineering and components that can be used in a circuit. They also possess analytical skills as they must be able to calculate loads, power consumption and sophisticated circuit architecture that involves cause and effects to produce sound results. With extensive knowledge of hardware engineering, Circuit Designers are responsible for hardware selection, board sizing, and routing of signals.
Here's some projects that our expert Circuit Designer made real:
These projects use both beginner and advanced electrical engineering techniques that our expert Circuit Designers are capable of delivering. With creativity, knowledge in engineering disciplines and product optimization experience, our Circuit Designers create reliable and innovative solutions for our clients’ projects.
We invite you to post your project on Freelancer.com so you can experience what our group of expert Circuit Designers have to offer. With their strong background in electronics engineering and creative problem solving, our freelancers can create dependable and optimized circuits for your project.
From 41,255 reviews, clients rate our Circuit Designers 4.84 out of 5 stars.Building a Catholic Prayer Chime Device — Electronics Design Phase We are developing The Angelus Chime, a battery-powered devotional device that plays authentic church bell recordings at 6 AM, 12 PM, and 6 PM. This is Phase 1 focusing exclusively on electronics design. IMPORTANT: This engagement delivers DIGITAL FILES ONLY — No physical prototypes, no assembly, no enclosure work. DEVICE OVERVIEW A sacred object for the home — a device that rings real church bells three times a day, as they have for 700 years across Europe. No app, no WiFi, no Bluetooth. Just bells. CORE FUNCTIONALITY Plays 2-3 minute church bell recordings at prayer times 3 toggle switches for each prayer hour Rotary switch for 8-12 bell recordings on SPI flash Volume control + large mute button Tim...
I am seeking a US-based hardware developer or electronics technician to assemble two physical prototypes of an RF-based proximity system. I have already developed the full source code and circuit schematics; however, due to a physical disability, I require a partner to handle the soldering, wiring, and physical housing of the components. Technical Requirements The project consists of two separate units: a Transmitter and a Receiver. Microcontrollers: Program and integrate 2x Arduino boards (provided/specified in schematics). Connectivity: Configure RF modules for proximity detection. Power: Integrate rechargeable battery systems (Li-Po or similar) with charging ports for both units. Assembly: Solder all components according to provided schematics. Enclosure: Mount...
Building a Catholic Prayer Chime Device — Electronics Design Phase We're developing The Angelus Chime, a battery-powered devotional device that plays authentic church bell recordings at 6 AM, 12 PM, and 6 PM. This is Phase 1 of a two-phase development strategy focusing exclusively on electronics design. IMPORTANT: This engagement delivers DIGITAL FILES ONLY - No physical prototypes - No assembly required - No enclosure work (handled in separate Phase 2) - Pure electronics design and firmware development DEVICE OVERVIEW A sacred object for the home — a device that sits on your mantel and rings real church bells three times a day, just as they have for 700 years across Europe. No app, no WiFi, no Bluetooth. Just bells. CORE FUNCTIONALITY - Plays 2-3 minute authentic chur...
Need getting Ionic Fingerprint from Saliva Need the schematic design circuit for this, with its components
1) Project goal Design a single PCB device for testing cable harnesses up to 25 wires, where both ends of the same harness are connected to the board: Side A: 25 lines (A1..A25) Side B: 25 lines (B1..B25) Total: 50 signal lines on the PCB. The detailed test logic (continuity/shorts/mapping) will be implemented in firmware later. For this phase, the key deliverable is robust hardware (schematic + PCB) prepared for such testing. 2) Scope of work (hardware only) Electrical schematic PCB layout Production files: Gerbers + drill BOM (with specs and acceptable alternatives) Assembly files (pick&place/positions) preferred Short mapping table: MCP23017 pins → A/B line numbers (Firmware is NOT required in this phase. Optional “I2C scan / basic blink” is a bonus.) 3...
I am midway through an online electrical training program and still have two graded components left in each module: the “learning activity” and the “content quiz.” Both are multiple-choice, can be retaken without limit, and I need a final score of 90 % or higher on every attempt that counts toward my record. You will receive screen-shots of every unfinished unit plus login access so you can work directly in the platform. Feel free to lean on AI tools or any personal reference material; the school places no restriction on outside resources. When you reply, please mention any hands-on electrical background, coursework, or certifications that show you can navigate these topics confidently. Deliverables • All remaining learning activities submitted with ≥...
My 4.5 V circuit needs a small solar panel and the proper charge-management hardware so daylight tops the battery up automatically. I’m not sure what panel voltage or wattage is best, nor which controller IC will keep the Li-ion safe—so I need your electronics expertise. Scope of work – I'll share my schematic of the existing 4.5v circuit – Select or design a charge-controller stage that handles lithium-ion chemistry, prevents over-charge/over-discharge, and outputs a stable 4.5 V rail to the load. – Provide a clear schematic, concise BOM with part numbers that are easy to source, and wiring instructions I can follow on perfboard or a small PCB. – Advise on any protection components (diodes, fuses, reverse-polarity safeguards) so the device...
I need an experienced electronics / PCB engineer to design a reliable 24/7 traffic light controller PCB. This is a safety-critical industrial system, not a hobby project. System Details: 220VAC traffic light LED modules Control via TRIAC (optocoupler + TRIAC driver) Continuous 24/7 operation ESP32-based control Fail-safe design required Industrial-grade AC mains design Using EasyEDA Requirements: Strong ESP32 hardware experience Experience with AC mains / TRIAC design Experience with industrial / high-reliability systems Comfortable designing fail-safe protection systems Timeline (strict): Day 1: Complete schematic Day 2: PCB placement & routing If it takes longer, it means you are not experienced enough — this is not a complicated project. You must be ready to...
I have five separate street-lighting circuits, each running roughly 1 km and powered by LED fixtures. For every run I must keep the voltage drop under 3 % . Your job is to size the conductors, select protective devices if required, and supply clear voltage-drop calculations that prove compliance for each feeder. Please base the work on standard RTA specs, and assume a three-phase, four-wire low-voltage supply 400V. Deliverables • Single-line or schematic for all five circuits showing conductor sizes and protection • Spreadsheet or calculation sheet detailing input data, formulas, and the final % drop for every circuit • Short narrative explaining any assumptions, cable grouping or ambient-temperature corrections applied I will review the numbers, confirm that no...
I need a medium complexity (3-4 layers) PCB designed for signal processing. The design should be capable of accommodating surface-mount components. Requirements: - 3-4 layers PCB design - Signal processing functionality - Surface-mount component integration - Gerber file generation Ideal Skills: - Experience with PCB design software (e.g., Altium, Eagle) - Strong understanding of signal processing circuits - Proficiency in layout for surface-mount components - Attention to detail and accuracy Please provide samples of previous work.
I have a finished KiCad PCB layout and now need a clean, print-ready PDF compiled from it. The final document must contain six A4 landscape pages arranged in this exact order: 1. Copper Top Layer 2. Copper Inner Layer 1 3. Copper Inner Layer 2 4. Copper Bottom Layer 5. Component Placement Top Layer 6. Component Placement Bottom Layer Resolution has to be crisp enough for both close-up review and high-quality printing. I’ll provide the KiCad source files as soon as we get started; you simply export each required layer, keep KiCad’s default rendering colours, and merge them into a single PDF. I’ve attached a previous example—please note the labels are mirrored on that file due to an earlier issue, so yours should read correctly. Deliverable • O...
Hello, I am looking for an experienced PCB designer to complete schematic review and PCB layout for an ESP32-based industrial IoT board using EasyEDA (Collaborator mode). Scope of Work 1. PCB Outline & Mechanical Alignment The PCB outline must match an existing device layout based on measurements and connector positions that I will provide. There is no reference Gerber file, so the board outline must be recreated carefully and confirmed with me before routing. 2. Schematic Review & Improvement (Important) You must review the schematic and confirm it is electrically correct and suitable for stable operation, including: Component ratings verification Power design validation Decoupling and grounding ESP32 stability considerations LM2596 switching regulator layout considerations Identi...
I need an existing wiring schematic revised to add one component. Requirements: - Current schematic is scanned from PDF - Need to add a green pilot light Ideal Skills: - Experience with wiring schematics - Proficient with PDF editing and schematic modification - Attention to detail and accuracy
I need the attached meter-layout sketch converted into a clean, professional one-line diagram showing the runs from the utility transformer to the meter pan. Label and conductor size must match the attached layout. Should include title block and sheet Deliverables: • PDF suitable for submission I’ll review the PDF against the template to make sure it's as requested; once it matches both, the project is complete.
I am developing a compact handheld consumer device prototype that requires integration of a rechargeable battery and small electronic module inside a custom 3D printed enclosure. I am looking for an experienced embedded hardware / electronics engineer who can help design and prototype a small, safe, battery-powered system suitable for a handheld form factor. The device will require: • Integration of a rechargeable lithium battery (3.7V or similar) • Safe charging system (USB-C or similar) • Small heating or vapor-generating element OR similar compact load component • Efficient power management and protection circuitry • Compact PCB design suitable for fitting inside a slim enclosure • Guidance on component selection and prototype assembly The enclosur...
I'm seeking an experienced AutoCAD designer specialized in 2D design for electrical control panels. Requirements: - Design control panels, including circuit breakers and switches - Modify existing designs and create new ones Ideal Skills: - Proficiency in AutoCAD, specifically for electrical designs - Experience with control panel design - Strong attention to detail and accuracy
I'm seeking an experienced AutoCAD designer specialized in 2D design for electrical control panels. Requirements: - Design control panels, including circuit breakers and switches - Modify existing designs and create new ones Ideal Skills: - Proficiency in AutoCAD, specifically for electrical designs - Experience with control panel design - Strong attention to detail and accuracy
I already have the full schematic and the finished PCB files for a board that combines an ESP module with a PIC18F microcontroller. What I’m missing is a clear, practical explanation of how everything talks to each other, especially over UART, and how that interaction is implemented on the physical board. Here is what I need from you: • A step-by-step walkthrough of the signal paths that handle UART traffic between the ESP and the PIC18F, including any level-shifting, buffering, or hand-shake lines that support the link. • A guided tour of the PCB layout that shows where those signals travel—layer changes, vias, ground references, decoupling, and any routing choices that affect integrity or noise. • Simple notes on any supporting circuitry (power rails, ...
I already have the full schematic and the finished PCB files for a board that combines an ESP module with a PIC18F microcontroller. What I’m missing is a clear, practical explanation of how everything talks to each other, especially over UART, and how that interaction is implemented on the physical board. Here is what I need from you: • A step-by-step walkthrough of the signal paths that handle UART traffic between the ESP and the PIC18F, including any level-shifting, buffering, or hand-shake lines that support the link. • A guided tour of the PCB layout that shows where those signals travel—layer changes, vias, ground references, decoupling, and any routing choices that affect integrity or noise. • Simple notes on any supporting circuitry (power rails, ...
I need solution for three questions electronics MATLAB/simulations file attached 1.35 1.36 1.39 Only induvial experts and tutors no agencies After this i will have so many projects Fair price flexible with time good availability of time
I'm seeking an engineer to create an intelligent mouse trap focused on monitoring and alerting. The trap should utilize a motion sensor for mouse detection and an actuator to trigger a trap upon detection. Key Requirements: - Motion sensor for detection - Actuator to trigger trap - Notification system for alerts Ideal Skills and Experience: - Experience with sensors and actuators - Knowledge in IoT and notification systems - Background in hardware development and prototyping Please share your relevant experience and approach.
I'm looking for an Arduino code that will trigger RGB LEDs to change color based on a pulse rotary dial input. Requirements: - Use of a pulse rotary dial - RGB LEDs whose colors will be controlled by the rotary dial input Ideal Skills and Experience: - Proficient in Arduino programming - Experience with rotary dials and RGB LED control - Familiarity with electronics and circuit design
Hello , I have a cabled weather station ready to go, but I need an experienced hand with the physical installation side only. The job covers everything from mounting the sensors and console, running and securing the cable, to making sure connections are weather-proofed, grounded, and reading correctly once powered up. Brand is flexible—I simply need someone familiar with the usual hardware found in systems such as Davis Instruments, AcuRite, La Crosse, or similar. Only serious freelancer Auto bids not good Thank you
I’m developing a compact medical-grade board that will sit at the heart of a new vital-signs monitor. The PCB must reliably acquire and process heart rate, blood pressure, and respiratory rate signals, then pass the data to a microcontroller for further analysis and display. Here’s what I need from you: • Complete schematic capture based on my sensor and MCU selections • Four-layer board layout optimized for low-noise biomedical signals (Altium or KiCad preferred) • Manufacture-ready Gerber files, pick-and-place data, and a clearly structured BOM with medical-grade component choices • Design reviews at schematic and pre-release layout stages so we can make sure the board meets IEC 60601-1/-2 spacing, leakage, and isolation requirements • Brief ...
I am looking for someone to develop hardware on my request, it will be simple projects as seen on you tube. I am interested to know hourly rates, if I provide the hardware and code they would just need to wire them up. Would be nice to have someone from India NCR.
I need a PCB designed specifically for a one-off project; it is not part of a commercial product line, so flexibility and creativity are welcome. The board will carry only analog circuitry—no digital sections—centred around operational amplifiers and a small signal-processing stage I will detail once we start. What I will supply: the schematic (PDF or KiCad), preferred footprints, and basic mechanical constraints. What I need from you: a clean, manufacturable layout with proper analog grounding practices, complete Gerber/ODB++ files, a reviewed BOM, and the original design file so I can revise it later if needed. Please aim for standard two-layer construction unless you advise otherwise for noise reasons. Acceptance will be based on: • DRC-clean files that import i...
The task is to design a compact PCB that drops straight into an SCX 1/32 car so it can run on a digital track. I want the board to read the track’s reed-sensor signal, let me assign any of 20 unique car IDs in firmware, and expose a surface-mount USB-C port on the edge for easy flashing once the body shell is back on. Size must stay close to the original analogue board footprint (about 24 × 18 mm, height under 6 mm) but I can adapt mounting holes or connector positions if you have a cleaner layout idea. Power comes from the standard track pickups (nominal 14–18 V DC), so include an efficient buck or LDO to feed the microcontroller and reed circuitry. I haven’t locked the MCU yet; pick anything small, inexpensive, and easy to program—ATmega, STM32, ESP32, or s...
I’ve drafted a single-layer board in Altium Designer and now need a seasoned set of eyes to run thorough simulations before I commit to building the first prototype. Your task is to import my project, verify the stack-up and component models, and perform all relevant electrical, thermal, and rule-check simulations available in Altium. Key goals • Confirm that signal integrity and power distribution meet design intent. • Flag any DRC or manufacturing issues early so I can correct them before fabrication. • Produce a concise simulation report summarizing the tests run, key plots or screenshots, and your recommendations. Deliverables 1. Updated Altium project files with all simulation settings preserved. 2. PDF or DOC report of findings and suggested fixes. ...
I need a compact, production-ready circuit that brings reliable wireless communication to a new consumer-electronics device. The work begins with schematic capture and component selection, moves through PCB layout, and finishes with ready-to-manufacture Gerbers, a complete BOM, and clear test guidelines. The radio link is the heart of the design, so careful RF layout, antenna matching, and regulatory-compliant power levels are essential. Bluetooth LE is my preferred protocol, though I am open to Wi-Fi or other 2.4 GHz solutions if you can demonstrate lower cost or better battery life without sacrificing performance. Please plan on: • Delivering editable design files in Altium, KiCad, or Eagle, plus PDFs for quick review • Calling out any critical components with long le...
I need a concise Python 3 script that will run on a Raspberry Pi 5 and do the following: • Watch a single GPIO input line for the HIGH digital signal coming from my Sony camera’s built-in AI output. • As soon as that digital signal is detected, drive a separate GPIO output that energises a small 5 V solenoid for five seconds, then automatically switch it off. • Debounce or otherwise ignore any further triggers until the five-second period is complete. The camera only provides a digital signal, so no protocol parsing is required—plain HIGH/LOW logic on the GPIO pin is all I need. The trigger itself must use the Pi’s native GPIO header rather than USB or networking. I haven’t fixed the exact GPIO numbers yet; feel free to suggest sensible default...
I'm seeking an experienced designer to create a 12V electrical panel for installation on the interior of a canopy. The panel will power lights, a fridge, and charging ports. Key requirements: - Incorporate a fuse box and circuit breakers for protection - Design must fit securely and function efficiently within the canopy interior Ideal skills and experience: - Expertise in 12V electrical systems - Experience with designing electrical panels - Knowledge of safety standards and protection mechanisms
I need an ebike throttle limiter that sits between the ebike throttle ( running 5v red, black (gnd) and white control wire and its controller : (DO NOT CUT these) Throttle RED (+5V) ------------------------------------ Controller RED (+5V) Throttle BLACK (GND) ------------------------------------ Controller BLACK (GND) (ONLY cut/switch the WHITE signal) Throttle WHITE (signal) ----+-----------------------------> Switch T1 | +----[ Rseries 1kΩ ]----+-----> Switch T2 = LIMIT NODE | +-----> Pot BLACK (wiper) Pot RED ---------------------------------------------> Controller...
I want to build a compact, two-way Bluetooth audio interface for a HAM radio. The core goal is a 2-way bridge between the radio and a realtime camera running on a linux board via buletooth. Digital or analog volume adjustment is needed Device must be battery and/or 12V DC operated, with DC12V charging battery if present What I need: • Full-duplex transmit and receive so both the radio’s microphone and speaker lines travel over Bluetooth. • A design that plays nicely with typical HAM radio mic/headphone levels. • Optional Radio PTT Sense to mute microphone input if PTT button not pressed • Stable pairing, clear voice quality, and minimal latency. Please provide: 1. Schematic and bill of materials (module choice is up to you; CSR, ESP32, or similar is fine). 2...
I already have a working ESP32 design in KiCad and need it brought to its final, production-ready form for a commercial product that must clear CE. The job centres on three key changes: swapping the Micro-USB for a USB-C connector, integrating a Li-Po charging IC, and tweaking the board outline and component placement so everything fits a new enclosure while preserving optimal antenna clearance, decoupling, and thermal performance. Please keep manufacturing constraints in mind and pass every KiCad DRC before delivery. Timeline is tight three days from award so I’m looking for someone who can move quickly yet meticulously. Deliverables • Updated KiCad project (schematic and PCB) • Fabrication package: Gerbers, drill files, BOM, and pick-and-place (CPL) ready for PCB...
I am looking for an experienced RF hardware designer to consolidate and miniaturize an existing RF system based on a MYIR Zynq-7020 board. The current setup includes: 1. MYIR Zynq-7020 board (fixed, no redesign) 2. Adapter board 3. Two separate RF transmitter boards The goal is to integrate the two RF boards and the Adapter board into a single compact adapter board, while keeping the existing electrical interfaces to the MYIR board unchanged and minimizing or avoiding FPGA/firmware changes as much as possible. Scope of Work (High Level) - Integrate two RF transmit chains on one board - Use a shared reference oscillator and PLL for both RF paths - Replace discrete RF filters with compact off-the-shelf RF filters - Replace legacy power regulators with modern, small LDOs - Add RF routing op...
I’m building a mini ventilator—an embedded medical device combining mechanical and electrical subsystems—and I’m looking for a dependable partner who can translate detailed specifications into working hardware and firmware. Your responsibilities will include hardware design, firmware development, and end-to-end integration and testing. How we’ll work: • I’ll provide clear, itemized requirements; you’ll convert them into schematics, PCB layouts, and clean, well-documented firmware. • We’ll maintain a tight feedback loop with regular progress updates, clarification where needed, and rapid iterations after reviews. • Accuracy, reliability, timelines, and strict confidentiality are non-negotiable. Expected deliverables (as appli...
I need an electronics specialist based in Mumbai who can take a lithium-ion battery management system from concept to a tested prototype. You will work with me locally so that component sourcing, quick iterations and on-site testing are easy. The circuit must reliably handle overcharge protection and intelligent load balancing across the pack. I am looking for you to create the full schematic, PCB layout and prototype on real lithium-ion cells in my lab and then hand over the working prototype plus and design files.
DESCRIPCIÓN: Busco estudiante o técnico de electrónica para realizar pruebas y validación de firmware en un proyecto real basado en ESP32. El firmware ya está desarrollado y estructurado. El trabajo consiste en: * Compilar firmware * Cargarlo en ESP32 * Realizar pruebas guiadas * Reportar resultados La arquitectura del sistema y el seguimiento técnico están organizados mediante asistencia de inteligencia artificial que ya conoce el proyecto completo y va indicando los pasos a ejecutar. El técnico no tiene que diseñar el sistema, solo ejecutar pruebas y reportar. QUE SE OFRECE: Este es un proyecto real que se está preparando para salir al mercado. Además de la remuneración, se ofrece: * Partic...
Projeto: Engenharia Reversa de Placa Eletrônica Legada Descrição do Projeto Busco profissional com experiência comprovada em eletrônica para realizar engenharia reversa completa de uma placa eletrônica legada, com o objetivo de: Reproduzir fielmente o funcionamento elétrico original Modernizar componentes obsoletos Gerar documentação técnica completa e atualizada Garantir compatibilidade mecânica, elétrica e funcional com o equipamento original O projeto seguirá um procedimento técnico estruturado já definido internamente Escopo do Trabalho O profissional deverá executar as seguintes etapas: 1. Análise e Correlação do Esquemático Verificaç&...
Ho già costruito alcuni prototipi di un circuito in grado di commutare un’unica linea da 230 V, 16–30 A, verso 4, 8 o 12 uscite; --senza perdita di potenza--, nessuno, però, raggiunge ancora gli standard che mi aspetto. Dispongo di schemi, calcoli, misurazioni termiche e log di prova: materiale sufficiente per chiarire ogni dettaglio tecnico e velocizzare il tuo lavoro. Mi occorre un progettista senior che sappia trasformare tutto questo in una soluzione definitiva, completa di firmware su ESP32, con PCB multilayer (4 o 6 strati, produzione JLCPCB - copper 3once) e una simulazione accurata e documentata prima della produzione. Requisiti tecnici da rispettare • Massima efficienza energetica, protezione dei componenti e precisione nella commutazione sot...
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