Capteur Qualité D'air Wi-Fi OLED

A room-level smart air quality monitor featuring an OLED display, Wi-Fi cloud connectivity, and USB power, housed in a robust 3D-printed standard enclosure.

Executive Summary

This reference design defines the system architecture, critical component candidates, risk register, and validation path for Smart Air Quality Monitor. It is a system-level design deliverable; verify critical claims with manufacturer evidence and prototype testing before production release.

Design Overview

Requirements Coverage

Requirement	Architecture coverage	Status
Surveillance d'une seule pièce (chambre ou salon)	Pending validation	Needs verification
Affichage OLED des données en temps réel	Pending validation	Needs verification
Connectivité Wi-Fi avec application mobile cloud	Pending validation	Needs verification
Capteurs de précision milieu de gamme	Pending validation	Needs verification

Item	Details
Product Type	Smart Air Quality Monitor
Key Functions	Surveillance d'une seule pièce (chambre ou salon), Affichage OLED des données en temps réel, Connectivité Wi-Fi avec application mobile cloud, Capteurs de précision milieu de gamme
Power Source	USB-C 5V
Connectivity	WiFi
Size	medium
Environment	indoor
Difficulty	Intermediate
Est. Time	3-4 hours

System Architecture

Power Topology: USB-C 5V → MCU 3.3V LDO

Module List

Module ID	Type	Name	Function	Voltage
POWER	POWER	USB-C Power Jack	Power input	5V
MCU	MCU	ESP32-WROOM-32	Main controller	3.3V

Power Tree and Signal Interfaces

From	To	Type	Interface / rail	Voltage
POWER	MCU	power	Power	-

Design Schemes

Smart Air Quality Monitor ★

Key IC selection

main MCU and wireless transceiver

• Need: Execute application firmware, interface with I2C/SPI sensors, drive OLED, and maintain stable 2.4GHz Wi-Fi connection to cloud
• Class: Wi-Fi + BLE Dual-Core SoC Module
• Shortlist: Espressif ESP32-WROOM-32, Realtek RTL8710AF family
• Pick: Select exact module variant based on flash size (e.g., 4MB or 8MB) and certification requirements for the target market

power input and regulation

• Need: Step down 5V from USB-C to stable 3.3V rails for MCU, sensors, and OLED display with low quiescent current
• Class: Low Dropout (LDO) Regulator or Buck Converter
• Shortlist: TPS62840 step-down converter, RT9013 low-noise LDO
• Pick: Choose based on thermal dissipation and efficiency requirements for a continuously plugged-in desktop device

Risk register

ID	Area	Severity	Detail	Mitigation
r1	thermal	med	Mid-range air quality sensors (such as VOC or particulate matter sensors) generate internal heat that can bias temperature and humidity readings inside a compact enclosure.	Ensure physical separation and adequate airflow vents between heat-generating components (like the power supply and Wi-Fi module) and the sensor cavity.
r2	emi	med	High-frequency switching noise from the power supply or digital noise from the OLED SPI/I2C interface can couple into sensitive analog/digital gas or particle sensor front-ends.	Implement proper grounding planes, adequate decoupling capacitors on power rails, and careful PCB routing keeping high-speed digital traces away from sensor analog lines.

Bring-up and Validation Plan

1. Power-off inspection and rail resistance checks
2. Current-limited first power-up; verify every rail before enabling loads
3. Validate interfaces and timing one subsystem at a time
4. Run thermal, fault-injection, EMC pre-scan, and endurance tests for the target environment

Key Components

2/2 modules matched to real parts. See the BOM tab for the full component table.

USB-C Power Jack (UJ20-C-H-G-MSMT-P16-TR)

The primary MPN is UJ20-C-H-G-MSMT-4B-P16-TR by 'Various'. Candidate 1 (index 1) is a very close variant from JST repres

ESP32-WROOM-32 (ESP32-WROOM-32)

The candidate MPN 'ESP32-WROOM-32' is an exact match for the primary MPN, matching both the manufacturer 'Espressif Syst

Build Summary

• Difficulty: Intermediate
• Estimated time: 3-4 hours
• Tools required: Soldering Iron, Solder Wire, Flux, Digital Multimeter, Precision Screwdriver Set, Flush Cutters

See the Build tab for the full step-by-step assembly guide.

Evidence and Limitations

• Confirm part parameters, certifications, and compatibility against current manufacturer documents.
• Treat industry compliance without test or certificate evidence as a compliance gap, not an approval.
• See Reference Images for visual artifacts and Build Guide for detailed assembly and bring-up steps.