Freelancer vs Upwork (2026)
Freelancer vs Upwork (2026) - An Honest, Side-by-Side Comparison for Businesses and Freelancers
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.
De 41,155 opiniones, los clientes califican nuestro Circuit Designers 4.9 de un total de 5 estrellas.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.
De 41,155 opiniones, los clientes califican nuestro Circuit Designers 4.9 de un total de 5 estrellas.I have a commercial IR-band Laser device with essentially two "Modes" - NORMAL and TRAINING, or restricted. Switching between the two can only be accomplished by accessing the Firmware via a proprietary 8-pin connection, for which I do not have a cable or interface. The candidate must either A) build a custom breakout to connect to the proprietary connector, or B) modify the OEM CONTROLLER pad and cable. Once the system is accessed, no custom coding, overwriting, or modification of the firmware will be required; the Candidiate need only identify the language, access the settings, and "flip the switch" between the two settings profiles. The hard part will be creating the connection. Something as simple as a POGO pin may be sufficient, but I am not qualified to say. T...
Project Title: Convert traced sketch to precise PCB outline CAD drawing (DXF) Description: I have attached a traced sketch of a PCB outline with component placement references. The drawing was created by tracing, so it is not dimensionally accurate. The freelancer must recreate it cleanly in CAD and scale it correctly. Key requirement: The top horizontal width must be exactly 100 mm. All other dimensions and proportions should be adjusted accordingly to match the sketch layout. Scope of work: Recreate the PCB outer profile with the same chamfered corners. Add the display window area, keypad slot, connector reference cutouts, and LED alignment positions as shown in the sketch. Place the mounting holes at the same positions indicated in the drawing. Use standard M3 mounting hole size ...
Title: Industrial PCB Design for Arduino-based 4-Pump Chemical Dosing System Description: I am looking for a professional PCB designer to create a robust, industrial-grade PCB for a chemical dosing system. The project is based on an Arduino Uno and must be designed to eliminate EMI noise from inductive loads. Key Technical Requirements: Microcontroller: Arduino Uno (Socketed on the PCB). Outputs: Control for 4x DC Pumps (24V) and 1x Solenoid Valve via Opto-isolated Relays. Power System: 24V DC Main Input with a Resettable Fuse (PPTC) for protection. Noise Immunity: Must include Flyback Diodes (1N4007) for each output and proper decoupling capacitors for logic stability. Isolation: Separate ground planes for Logic (5V) and Power (24V) to prevent interference. External Interface: Hea...
I need an expert to set up Ignition SCADA and integrate it with one Allen-Bradley CompactLogix PLCs for monitoring an existing process. In addition we need a panel designed and integrated that will monitor compressed air and nitrogen. This will need to be SCADA integrated as part of implementation and visualization. We will need Allen Bradley / CompactLogix setup. Key Requirements: - Set up a new Ignition SCADA system - Integrate one existing CompactLogix PLCs/HMI panel/process - Design/Implement a new PLC/panel to monitor compressed air and nitrogen levels Ideal Skills: - Proficiency in Ignition SCADA - Experience with Allen-Bradley CompactLogix PLCs - Ability to design panels - Strong background in industrial automation and monitoring systems Please provide a detailed plan and timeli...
We need a board that "translate" signal from DMX to led strip pixel adressable. Need to integrate RGB and RGBW pixel in various protocol, with clock or only data. Only one data signal needed (170 rgb pixel or 128 rgbw pixel to complete universe) -Possibilities to set start adress -Possibilities to control multiple pixel as one pixel (grouping for have total of 2x or 3x o 4x pixel controlled) -Setting IC ,Address and Grouping by dipswitch or other way accepted (also usb serial with proprietary software) -ALL SETTINGS NEED ALSO TO BE SETTED BY RDM -Usb or serial connector for upload firmware We are open to every system from arduino to anything. Need to be thinked in hardware and software side. Other this one we need a variant with pwm rgbw output with same feature like RDM, ...
I need a double-layer, signal-processing board laid out in Altium Designer and prepared for fabrication at JLCPCB. The finished board will fit inside a 15 cm × 15 cm envelope, so component placement, routing, and keep-outs should respect that medium-size constraint. Deliverables I expect: • Complete Altium project with schematics and PCB layout • Optimised Gerber, drill, and pick-and-place files matched to JLCPCB’s specs • BOM with manufacturer part numbers and assembly notes I will review the design by importing the files directly into Altium and running JLCPCB’s online DFM check; the job is complete once the files upload without errors and the board passes ERC/DRC.
I need the internal circuitry of the KK-82MS scientific calculator documented so I can design a drop-in replacement PCB. Your job is to open the unit, trace every relevant signal, and give me a clear map of what connects where. The focus is on both LCD behaviour and the button-scanning scheme, so I expect you to show how each LCD segment is driven, which pins act as commons, how the microcontroller multiplexes them, and the exact keyboard matrix rows and columns the processor polls. Feel free to combine a logic analyser, multimeter, oscilloscope, or any other bench tool you trust; choice of instrumentation is up to you as long as the final data are unambiguous. Deliverables • High-resolution photos of the calculator fully disassembled, including close-ups of the flex cables and IC m...
Hi, I'm looking for an experienced PCB designer to create a custom carrier/breakout PCB for a compact handheld device. No firmware or software needed — design only. Core Module: LILYGO TTGO T-Call V1.3 (ESP32 + SIM800L GSM) — mounted on the PCB via pin headers Components to integrate on PCB: OLED Display (SSD1306 128x64, I2C, 4-pin): Mounted above the PCB using standoff spacers — 4 mounting holes required Height will be adjusted with standoffs 4-wire cable from display soldered directly to PCB pads Buttons: 1x membrane switch connector (2-pin) for main button 2x additional button footprints connected to spare GPIO pins (for future use) Buzzer: Passive buzzer mounted directly on PCB Connected to designated GPIO via NPN transistor + flyback diode driver circuit ...
My Denon AVR drives a home theater system, and the moment the amplifier powers up the speakers erupt with a rolling, thunder-like rumble. The noise stops only when the unit is switched off. All speaker wires, RCA leads, HDMI runs, and power connections have been double-checked and seated firmly, so loose cabling does not appear to be the culprit. I’m looking for an experienced audio-electronics technician who can come on-site, trace the fault, and advise on the fix—whether that turns out to be a failing power-supply capacitor, a grounding issue, or something deeper on the amplifier’s main board. If parts need ordering, I’m happy to approve them once the underlying cause is confirmed. Please let me know: • Your house-call availability in the next week or ...
I'm seeking an expert to prototype the electric chassis wiring for an electric trolley designed to transport tools. Key requirements include: - Design and implement wiring for electric chassis - Ensure safety and reliability Ideal skills and experience: - Electrical engineering background - Experience with electric vehicle wiring - Strong problem-solving skills Please provide relevant experience in your bids.
I want to build a persistence-of-vision LED system that mounts on a standard bicycle wheel and shows crisp, full-color static images whenever the wheel reaches riding speed. The image should appear only at higher RPMs—cruising or sprint speeds—not while I am moving slowly or stopped. Core functionality • An addressable 256 LED spoke mounted strip driven by a small micro-controller (ESP32, Arduino-compatible, or similar) and powered by a lightweight, wheel-mounted battery. • Firmware that stores and renders static bitmaps in correct perspective as the wheel spins, synchronizing via hall-effect or magnet sensor. • A simple phone app that lets the rider pick any image, crop it to a wheel-friendly template, and wirelessly push it to the controller. There is no...
I need a custom power supply designed specifically for consumer electronics, with a focus on automation systems. The power supply must output 12V. Key requirements: - Suitable for consumer electronics and automation systems. - 12V output voltage. Ideal skills and experience: - Expertise in power supply design. - Experience with consumer electronics and automation systems. - Knowledge of safety standards and regulations. Please provide your portfolio and relevant experience.
Job Title: Electrical Design for Residential + Commercial Building (Indoor, Outdoor, DG Backup, Fire Pump & Lift) Project Description I am looking for an experienced Electrical Design Engineer to prepare a complete electrical design package for a Residential + Commercial building project. The design must include indoor and outdoor electrical systems, emergency lighting, DG backup systems, fire pump electrical supply, lift supply, inverter backup lines for apartments, conduit routing, and BOQ preparation. Design must comply with NBC India, IS standards, and standard electrical engineering practices. --- Scope of Work 1. Indoor Electrical Design - Lighting layout for apartments, commercial areas, corridors, staircases, and common areas - Power layout including switches, sockets, ...
Freelance Hardware Engineer – Altium PCB Design Review (Remote Access) We have an existing Pulse Converter PCB designed using Altium Designer and are looking for an experienced freelance hardware / PCB design engineer to perform a technical design review. The work will be done via remote access to our computer (AnyDesk / TeamViewer). Design files will not be shared. Detailed circuit functionality and design context will be explained after mutual agreement and confidentiality alignment. Scope of Work: Review the schematic and PCB layout in Altium Designer and identify potential design issues, risks, and improvement points, including but not limited to: Power input and regulation (wide-range DC input) Relay driver circuits Optocoupler-based pulse input circuits MCU (ESP32 or sim...
I need a robust arc-suppression circuit engineered specifically for my RF welding machine. The goal is simple and non-negotiable: stop destructive arcing before it reaches the generator or matching network, protecting the entire system from costly downtime and repairs. Key points you should know up front • Purpose: prevention of equipment damage only—operator safety circuits are handled elsewhere. • Architecture: solid-state components throughout; no relays or mechanical contacts. • Ratings: I will share the operating voltage and current range once we start, so your design must be adaptable within those limits. What I expect to receive 1. Schematic with clearly labeled protection stages (detection, quench, reset). 2. Bill of materials with manufacturer p...
I need five separate input-output matching networks for the MACOM CGHV270305, one for each of the following RF bands: • 30–200 MHz • 200–600 MHz • 600 MHz–1.8 GHz • 1.8GHz–4 GHz • 4GHz–6 GHz For every band the network must deliver at least 30 W across the full span while maintaining solid, stable gain. I will verify this from the final performance plots, so please present both power-output and gain data together in clear scatter-plot format. Alongside the simulation results I need production-ready DXF files of the matching PCB layouts. Keep the drawings aligned with recognised industry standards so they can move straight into fabrication without extra re-work. Deliverables 1. S-parameter models (touchstone) and any suppor...
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. . The Sony camera will be pre-loaded with images of the target - in this case a plant which is detected in the target bounding box in the camera field of view. . When the target plant is encountered in bounding box of the camera field of view, the corresponding relay will activate a spray nozzle for the time the target remains in the bounding box. •The point above is achieved as soon as that digital signal is detected, drive a separate GPIO output that energises a small 5 V solenoid for as long as the target plant remains in the bounding box of the camera, then automatical...
PCB DESIGN with these or better components placement Processor & Memory Main SoC NXP iMX8M Plus — Quad Cortex-A53 1.8GHz + Cortex-M7 800MHz Safety MCU TI TMS570LS3137 — dual-core lockstep Cortex-R4F, SIL-2 certified Diag FPGA Lattice MachXO3LF-9400 — in-situ verification logic, <2ms latency RAM 4 GB LPDDR4, ECC enabled, 1600 MT/s Flash 32GB eMMC 5.1 (AES-256-XTS) + 128MB QSPI NOR boot Wireless MCU ESP32-S3 co-processor (Wi-Fi 6) Sensor Specifications Temperature PT1000 ±0.05°C (primary), DS18B20 ±0.5°C (backup), NTC (tertiary). Range: −40 to +150°C Humidity SHT45 ±1.0%RH + HDC3020 ±1.5%RH. Range: 0–100%RH, 0–85°C Pressure MS5837-02BA 0–2bar ±0.05%FS + MS5837-30BA 0–30bar (secondary) L...
Project Title: Miniature Piezo Preamp PCB (10mm) – Reverse Engineer & Redesign Project Overview I am developing a professional leak detection microphone used for plumbing diagnostics. The system uses a piezoelectric sensor to detect vibration and sound from water leaks inside pipes. I already have a working preamp circuit, but the PCB is too large for my application. I need an experienced electronics engineer to analyze the existing design and redesign it into a much smaller PCB. The new design must maintain similar electrical performance but reduce the physical size so it can be mounted directly on the piezo sensor and permanently sealed with epoxy resin inside a capsule. Primary Objectives 1. Analyze or replicate the functionality of my existing piezo preamp. 2. Redesign ...
I am looking for an experienced PCB designer to create a 4‑layer carrier board for a Raspberry Pi Compute Module 5 (CM5). The board integrates several existing open‑source hardware concepts into a single PCB, with limited original R&D but careful integration and cleanup. Scope of this first project - Review and consolidate existing reference schematics (I will provide open‑source designs and documentation). - Design the final schematic for: - Raspberry Pi CM5 + power supply - CAN‑based bus for a marine/industrial network (NMEA‑style) - NMEA 0183‑style serial interfaces - Connectors and I/O suitable for a small boat/embedded environment - eDP interface for an external display - PCB layout: - 4‑layer stackup with proper impedance control for eDP - Rea...
I am building a tiny GPS tracker device for my company and need an experienced PCB designer. Project Requirements: - Design schematic and PCB layout for a compact GPS tracker. - Use SIM7080G (LTE/NB-IoT with GNSS) module. - Include SIM card slot, GPS antenna connector, LiPo battery connector, and charging circuit. - Board size should be approximately 18 mm x 20 mm. Deliverables: - Complete schematic - PCB layout - Gerber files for manufacturing - Bill of Materials (BOM) - Pick and Place file (optional) Preferred Tools: KiCad, Altium Designer, or EasyEDA. Experience Required: - Experience designing IoT or GPS tracking devices - Knowledge of RF layout and antenna placement Budget: $30 – $50 (negotiable) Please share examples of previous PCB designs.
I’m ready to move an industrial-grade controller from concept to production and need a designer who has already shipped tight, 6-layer boards. The board must host a main microcontroller, its support circuitry, and several high-current power-regulator stages, all within a restricted outline while meeting EMI/EMC limits typical for factory environments. You’ll start from my block diagram and rough schematic notes, turn them into a production-ready layout, and supply every file the assembly house will ask for: updated schematics, stack-up, Gerbers, drill files, pick-and-place, BOM, and a brief design report explaining how the EMC strategy and size targets were achieved. I’ll be available for rapid feedback on component placement and routing choices, and we’ll sign ...
Title: Transformer Design Engineer Needed – Oil Filled Distribution & Solar Transformers Description: We are setting up a transformer manufacturing unit in Vadodara, India and are looking for an experienced electrical design engineer with expertise in oil-filled power/distribution transformers. This is initially a freelance/consulting role to help us develop transformer designs and technical documentation for manufacturing. Scope of Work: • Design of oil-filled distribution transformers (25 kVA – 100 kVA, 11kV / 433V) • Design of solar inverter duty step-up transformers (250 kVA – 500 kVA, 415V / 690V to 11kV) • Preparation of transformer design calculations (core size, winding design, impedance, losses etc.) • Preparation of GA drawings...
Description Of Project - HRID-AI is a low cost handheld device aimed at estimating ejection fraction using multimodal biosignals (ECG, seismocardiography, and cardiac acoustics). It uses a combination of biosensors to detect abnormalities in ECG, presence of abnormal heart sounds and their interpretation as well as usage of seismocardiographic signals to provide an estimate of Ejection Fraction. The principle has been verified through multiple studies done in reputed institutions The goal is rapid point-of-care triage for echo referral in emergency and low-resource settings in patients of Heart Failure with Reduced Ejection fraction We need your support, skills and expertise for sensor integration, embedded design, signal acquisition. Current Status- We have so far been able to dev...
We need an electronics engineer to implement a PCB design based on an existing schematic for a renewable energy monitoring project. The system measures electrical parameters from multiple sources including a solar panel, wind turbine, battery, and inverter output. The schematic already exists in PDF format and includes components such as Arduino Nano Every, MCP3903 ADC, ADS1115, WCS1600 current sensors, and HC-12 communication module. The task is mainly to follow the existing schematic, verify the design, and create a manufacturable PCB layout.
I will provide the full Proteus project (schematic, PCB, libraries). Your task is to recreate that board in Altium Designer as an exact, bit-for-bit copy—same dimensions, traces, footprints and reference designators—so the migrated file can drop-in-replace the original. Once the design lives in Altium, prepare a complete production package for JLCPCB consisting of: • Gerber set generated with Altium’s CAM outputs • Pick-and-place centroid file (CSV) referenced to the board origin JLCPCB expects • Clean BOM that matches the Altium project and includes LCSC part numbers and JLCPCB’s preferred column headings Please keep the design locked as-is; no routing or placement tweaks. Organise the schematic sheets and PCB libraries so I can add compo...
I need an experienced PCB programmer to reprogram a multi-layer PCB for a coffee maker. The board is used for a coffee maker. Required Skills and Experience: - Proficiency in reprogramming multi-layer PCBs - Experience with radio frequency (RF) applications - Knowledge in embedded systems - Familiarity with brewing settings, temperature control, timing and scheduling, and pump control functionalities
I have an Arduino-based board that is powered from its own DC rail, yet it has to monitor several other DC lines whose grounds are completely separate. Right now I’m simply feeding each line through a voltage divider, and—unsurprisingly—the readings jump around or drift because the grounds are floating. The symptom is clear: inaccurate voltage readings that make the data unusable. What I need is a clean, reliable way to sense those isolated DC voltages without tying the reference points together. Whether that means introducing isolated amplifiers, optocouplers, tiny transformers, or another proven technique is up to you; I’m open to whichever approach gives stable, repeatable results and keeps the measurement side safe for the microcontroller. Here’s what I&...
I need an experienced PCB designer to edit an existing single-sided PCB design. The current design is in Altium and requires modifications for testing and validation. Requirements: - Change component placement - Route traces Ideal Skills and Experience: - Proficiency in reading and editing Altium - Experience in PCB design, especially for testing purposes - Attention to detail and precision Please provide examples of previous work.
I need help turning three off-the-shelf modules now sitting in my glasses prototype—a USB 2.0 hub, a USB audio codec (mic plus stereo out) and a dual-channel Class-D amplifier—into one long, narrow board that can slide inside the temple arm. The space I have measured is roughly 80 mm × 15 mm, so the layout has to be linear rather than squarish, with components placed to keep the height profile as low as practical. The board will run exclusively from the host’s 5 V USB rail; no batteries or additional supplies are planned. Because this is for voice prompts and basic media playback, a standard-grade codec is fine—I’m not chasing audiophile specs, just dependable microphone input and clean stereo output that won’t hiss or pop when the amp is idle. A...
Description Of Project - HRID-AI is a low cost handheld device aimed at estimating ejection fraction using multimodal biosignals (ECG, seismocardiography, and cardiac acoustics). It uses a combination of biosensors to detect abnormalities in ECG, presence of abnormal heart sounds and their interpretation as well as usage of seismocardiographic signals to provide an estimate of Ejection Fraction. The principle has been verified through multiple studies done in reputed institutions The goal is rapid point-of-care triage for echo referral in emergency and low-resource settings in patients of Heart Failure with Reduced Ejection fraction We need your support, skills and expertise for sensor integration, embedded design, signal acquisition. Current Status- We have so far been able to dev...
I need a self-contained unit that lets me key a number on a small touch screen and see that exact value appear instantly on a free-standing LED numerical tower. The goal is true plug-and-play functionality: once mains power is connected, the system should be ready without additional setup, drivers, or calibration. Core requirements • Input: a touch-screen number pad that accepts whole numbers (ideally up to four digits). • Display: an LED tower that shows the number in bright, easily readable digits; the tower must refresh in real time as I enter or change the value. • Form factor: bench-top or floor-standing, compact enough for shop-floor use, with a single power lead and a secure data link between screen and tower. • Reliability: stable operation for 8+ hours...
I need an experienced PCB designer to edit an existing single-sided PCB design. The current design is in Altium and requires modifications for testing and validation. Requirements: - Change component placement - Route traces Ideal Skills and Experience: - Proficiency in reading and editing Altium - Experience in PCB design, especially for testing purposes - Attention to detail and precision Please provide examples of previous work.
Embedded Hardware & Firmware Expert Needed for Industrial 3-Phase Pure Sine Wave Inverter Project Overview: I am seeking an experienced Power Electronics and Embedded Systems Engineer to design the hardware and firmware for an Industrial-Grade 3-Phase Pure Sine Wave Inverter. The project involves designing multiple PCBs (MCU Motherboard, IGBT Driver, Thyristor Driver, and Sensing Interface) and developing robust firmware for system control, monitoring, and HMI integration. 1. Hardware Specifications & PCB Requirements: You will be responsible for designing the following industrial-grade PCBs: • MCU Motherboard: Based on Texas Instruments (TI) or Microchip architecture. Must handle PWM modulation and system logic. • IGBT Driver PCB (3-Phase): Industrial grade, optimized fo...
Freelancer vs Upwork (2026) - An Honest, Side-by-Side Comparison for Businesses and Freelancers
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