Turnkey ESP32-S3 Travel IoT PCB with Enclosure Design
Budget: $150 – $600 USD
Senior Hardware Engineer: Turnkey ESP32-S3 PCB Design (18x35mm)
Project Overview
I am seeking a senior hardware engineer to design a professional, 4-layer, double-sided PCB for a high-performance travel IoT device. This device acts as an IR blaster, local AI audio monitor (for volume/occupancy), and environmental sensor.
Completion Criteria: This is a turnkey electrical project. The project is considered complete only after I have physically tested the manufactured boards and validated that all sensors, voice features, and power circuits work as specified.
Core Hardware Specifications
MCU: ESP32-S3-WROOM-1U-N16R8 (16MB Flash / 8MB PSRAM).
Antenna: U.FL connector for external flex-film antenna.
Dimensions: Strict 18mm x 35mm footprint.
Storage: Molex 104031-0811 MicroSD socket (Push-pull).
Sensors: Bosch BME690 (AQI/Temp) and 2x TDK MMICT5838-00-012 (Bottom-ported I2S Mics).
IR LEDs: 1x Top-firing and 1x Side-firing right-angle (940nm, high-power).
Expansion Port: 1x JST-SH 1.0mm 4-pin port. M5Stack/Grove compatible: Pin 1: GND, Pin 2: 5V (tolerant), Pin 3: SDA, Pin 4: SCL.
Power: Mid-mount USB-C plug (sunk into PCB to minimize total Z-height for an 8mm enclosure goal).
Privacy/UI: 1x Physical Slide Switch (to hardware-disconnect power to the mics) and 1x WS2812B-2020 RGB LED for status feedback.
Control: 2x micro SMD tactile buttons (BOOT/RESET).
Engineering & Audio Requirements
Acoustic Pathing: Design proper unplated through-holes (min 0.5mm) for the bottom-ported MEMS microphones. Mics must be placed at opposite ends of the 35mm length to optimize Acoustic Echo Cancellation (AEC).
Thermal Logic: The BME690 must be thermally isolated from the ESP32 and LDO via PCB cutouts/milled slots to ensure accurate ambient temperature readings.
Power Design: N-Channel MOSFET drivers for IR LEDs powered directly from the 5V line for maximum range.
Layout: 4-layer stackup with a dedicated ground plane. Components must be placed on both sides to achieve the minimalist footprint.
Manufacturing Deliverables (The "Easy-Order" Package)
The engineer must provide a complete manufacturing folder designed for seamless "one-click" ordering via providers like PCBWay or JLCPCB:
Design Files: Native CAD (KiCad or Altium) and Schematics.
Production Files: Gerbers (RS-274X or X2), NC Drill, and Centroid/Pick-and-Place files with correct part rotations for automated SMT.
BOM: CSV/Excel file mapped to active LCSC or DigiKey part numbers.
3D Model: A high-fidelity .STEP file of the fully populated PCB. This is critical for future enclosure development.
Documentation: A brief pin-mapping guide (PDF/Markdown) for firmware development.
Application & Bidding Rules
To be considered, you must begin your proposal with the exact phrase: "Turnkey 18x35".
No Placeholder Bids: I expect a firm, realistic quote for the full scope (EE + ME). Do not bid a low price simply to open a chat and ask for my budget.
Experience: Preference given to engineers with a portfolio of sub-25mm dense IoT devices and experience with M5Stack or the Espressif speech-recognition framework.
Project Overview
I am seeking a senior hardware engineer to design a professional, 4-layer, double-sided PCB for a high-performance travel IoT device. This device acts as an IR blaster, local AI audio monitor (for volume/occupancy), and environmental sensor.
Completion Criteria: This is a turnkey electrical project. The project is considered complete only after I have physically tested the manufactured boards and validated that all sensors, voice features, and power circuits work as specified.
Core Hardware Specifications
MCU: ESP32-S3-WROOM-1U-N16R8 (16MB Flash / 8MB PSRAM).
Antenna: U.FL connector for external flex-film antenna.
Dimensions: Strict 18mm x 35mm footprint.
Storage: Molex 104031-0811 MicroSD socket (Push-pull).
Sensors: Bosch BME690 (AQI/Temp) and 2x TDK MMICT5838-00-012 (Bottom-ported I2S Mics).
IR LEDs: 1x Top-firing and 1x Side-firing right-angle (940nm, high-power).
Expansion Port: 1x JST-SH 1.0mm 4-pin port. M5Stack/Grove compatible: Pin 1: GND, Pin 2: 5V (tolerant), Pin 3: SDA, Pin 4: SCL.
Power: Mid-mount USB-C plug (sunk into PCB to minimize total Z-height for an 8mm enclosure goal).
Privacy/UI: 1x Physical Slide Switch (to hardware-disconnect power to the mics) and 1x WS2812B-2020 RGB LED for status feedback.
Control: 2x micro SMD tactile buttons (BOOT/RESET).
Engineering & Audio Requirements
Acoustic Pathing: Design proper unplated through-holes (min 0.5mm) for the bottom-ported MEMS microphones. Mics must be placed at opposite ends of the 35mm length to optimize Acoustic Echo Cancellation (AEC).
Thermal Logic: The BME690 must be thermally isolated from the ESP32 and LDO via PCB cutouts/milled slots to ensure accurate ambient temperature readings.
Power Design: N-Channel MOSFET drivers for IR LEDs powered directly from the 5V line for maximum range.
Layout: 4-layer stackup with a dedicated ground plane. Components must be placed on both sides to achieve the minimalist footprint.
Manufacturing Deliverables (The "Easy-Order" Package)
The engineer must provide a complete manufacturing folder designed for seamless "one-click" ordering via providers like PCBWay or JLCPCB:
Design Files: Native CAD (KiCad or Altium) and Schematics.
Production Files: Gerbers (RS-274X or X2), NC Drill, and Centroid/Pick-and-Place files with correct part rotations for automated SMT.
BOM: CSV/Excel file mapped to active LCSC or DigiKey part numbers.
3D Model: A high-fidelity .STEP file of the fully populated PCB. This is critical for future enclosure development.
Documentation: A brief pin-mapping guide (PDF/Markdown) for firmware development.
Application & Bidding Rules
To be considered, you must begin your proposal with the exact phrase: "Turnkey 18x35".
No Placeholder Bids: I expect a firm, realistic quote for the full scope (EE + ME). Do not bid a low price simply to open a chat and ask for my budget.
Experience: Preference given to engineers with a portfolio of sub-25mm dense IoT devices and experience with M5Stack or the Espressif speech-recognition framework.