ESP32 Indoor Air Quality Module

1:22

Planning PCB Development.

Your goal is to implement the exact 55×45 mm, 2‑layer ESP32‑C5 IAQ monitor with USB‑C, OLED, PMS7003, STCC4+SHT41, and a common‑anode RGB LED, then export all files.

Plan to execute:
1. Add all parts/passives and programming pads; lock USB D−=GPIO13, D+=GPIO14; avoid strap pins; IO15 unused.
2. Wire schematic exactly per your netlist (I2C pulls, STCC4↔SHT41 bus, PMS UART on GPIO23/24, RGB LED resistors to GPIO6/9/10, EN RC, CC 5.1k, ESD).
3. PCB layout: 55×45 mm, strict antenna keep‑out both layers; power block by USB‑C; sensors at edge and ≥10–15 mm from LDO/MCU; solid bottom GND; labeled test pads.
4. Reviews & exports: ERC/DRC, availability; verify strap rules; export schematic PDF, BOM CSV, Gerbers+drill, P&P; compile review notes.
Note: Based on Flux knowledge base guidance, I will include programming pads (U0TXD GPIO11, U0RXD GPIO12, EN, GPIO28, 3V3, GND) for reliable post‑assembly flashing.

Click Start on the plan bar to begin execution.

Plan

#Goal

Design a USB‑powered, 55×45 mm, 2‑layer ESP32‑C5 IAQ monitor board integrating STCC4+SHT41, PMS7003 (UART), SSD1306 OLED (I²C), a common‑anode RGB LED, and complete power/protection circuitry (AP2112K‑3.3 LDO, polyfuse, USBLC6‑2SC6 ESD). Adhere to USB pin locks (USB D− as GPIO13, D+ as GPIO14), avoid strap pins, leave IO15 unused, and isolate the SHT41 to the STCC4 bus. Include labeled test points and programming pads for U0TXD (GPIO11), U0RXD (GPIO12), EN, GPIO28, 3V3, and GND, ensuring a production-grade design suitable for IAQ monitoring.

#Implementation plan

Component Selection and Schematic Setup
1. Select and add the ESP32‑C5‑WROOM‑1‑N8R4, ensuring USB pin assignments are locked: USB D− to GPIO13 and USB D+ to GPIO14.
2. Add the STCC4 (STCC4-D-R3) and configure it as the exclusive compensation bus for the SHT41 sensor (SHT41‑AD1B‑R3).
3. Add the PMS7003 sensor, wiring its TXD to GPIO23, RXD to GPIO24, and SET to GPIO8 via a dedicated 1×6 header.
4. Add the SSD1306 OLED display using a 1×4 header; route I²C on GPIO4 and GPIO5 with 4.7kΩ pull-ups to the 3V3 rail.
5. Include the ASMB‑MTB1‑0B3A2 common‑anode RGB LED. Connect its anode to 3V3 and add 680Ω resistor for red on GPIO6, and 220Ω resistors for green and blue on GPIO9 and GPIO10 respectively.
6. Incorporate power supply components: USB‑C connector with CC configuration (5.1kΩ resistor to GND), polyfuse, AP2112K‑3.3 LDO, and USBLC6‑2SC6 for USB ESD protection.
7. Add labeled test points and programming pads for U0TXD (GPIO11), U0RXD (GPIO12), EN, GPIO28, 3V3, and GND.
Schematic Wiring and Net Connections
1. Connect the USB‑C connector: wire CC with a 5.1kΩ resistor to GND, route D− through ESD to GPIO13 and D+ through ESD to GPIO14.
2. Wire the power path: route USB‑C VBUS through the polyfuse to the input of the AP2112K‑3.3 LDO, providing the 3V3 rail.
3. Connect I²C signals from ESP32‑C5 GPIO4/5 to both the OLED and the SHT41 (via the STCC4 bus), using 4.7kΩ pull-ups.
4. Wire the PMS7003 sensor to the UART pins as specified and ensure proper connection for the SET line.
5. Route connections for the RGB LED with designated resistors from the respective GPIO pins to the LED cathodes.
PCB Layout and Mechanical Considerations
1. Set the board dimensions to 55×45 mm and ensure a strict two-layer design.
2. Define and reserve an antenna keep‑out area for the ESP32‑C5 across both layers.
3. Place the USB‑C connector and power block near each other for minimal power routing length.
4. Position sensors (SHT41 and PMS7003) near the board edge (at least 10–15 mm away from other power components), and group labeling for test points and programming pads along the board perimeter.
5. Ensure decoupling capacitors are placed close to the MCU’s power pins for optimal performance.
Design Review and Output Generation
1. Run ERC/DRC to confirm net connections, strap pin compliance, and proper avoidance of IO15 usage and unwanted strap pins.
2. Verify that all components (including sensor and I/O headers) are correctly oriented and that test points and programming pads are clearly labeled.
3. Export final deliverables: schematic PDF, BOM with MPNs, Gerbers, drill files, and pick & place file.
4. Compile design review notes focusing on power routing, antenna keep‑out, ESD protection, and proper test pad placements.

#Success criteria

All specified components are correctly selected, added, and interconnected per requirements.
USB‑C connections enforce the pin locks (GPIO13 for D−, GPIO14 for D+), with avoided strap pins and unused IO15.
Complete generation of design outputs: schematic PDF, BOM CSV, Gerber files, drill, and pick & place files with appropriate labels and test points.
PCB layout adheres to a 55×45 mm size, with correct component placement, defined antenna keep‑out, and proper power management.

Start with symbols and footprints

Lock in the USB-C and protection

Clarify PMS7003 header pin order

Help with EN/BOOT circuitry details

Ask about routing constraints

116 days

Reviews

Ground
A common return path for electric current. Commonly known as ground.
jharwinbarrozo
20.5M
Net Portal
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
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43.0M
Power Net Portal
Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #power
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11.4M
Generic Resistor
A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Generic Capacitor
A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF, 10pF, 100pF, 1000pF, 0.01uF, 0.1uF, 1.0uF, 10uF, 100uF, 1000uF, 10000uF 1.1pF, 11pF, 110pF, 1100pF 1.2pF, 12pF, 120pF, 1200pF 1.3pF, 13pF, 130pF, 1300pF 1.5pF, 15pF, 150pF, 1500pF, 0.015uF, 0.15uF, 1.5uF, 15uF, 150uF, 1500uF 1.6pF, 16pF, 160pF, 1600pF 1.8pF, 18pF, 180pF, 1800pF 2.0pF, 20pF, 200pF, 2000pF 2.2pF, 22pF, 220pF, 2200pF, 0.022uF, 0.22uF, 2.2uF, 22uF, 220uF, 2200uF 2.4pF, 24pF, 240pF, 2400pF 2.7pF, 27pF, 270pF, 2700pF 3.0pF, 30pF, 300pF, 3000pF 3.3pF, 33pF, 330pF, 3300pF, 0.033uF, 0.33uF, 3.3uF, 33uF, 330uF, 3300uF 3.6pF, 36pF, 360pF, 3600pF 3.9pF, 39pF, 390pF, 3900pF 4.3pF, 43pF, 430pF, 4300pF 4.7pF, 47pF, 470pF, 4700pF, 0.047uF, 0.47uF, 4.7uF, 47uF, 470uF, 4700uF 5.1pF, 51pF, 510pF, 5100pF 5.6pF, 56pF, 560pF, 5600pF 6.2pF, 62pF, 620pF, 6200pF 6.8pF, 68pF, 680pF, 6800pF, 0.068uF, 0.68uF, 6.8uF, 68uF, 680uF, 6800uF 7.5pF, 75pF, 750pF, 7500pF 8.2pF, 82pF, 820pF, 8200pF 9.1pF, 91pF, 910pF, 9100pF #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Generic Inductor
A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
jharwinbarrozo
15.8k
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
RMCF0805JT47K0
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
jharwinbarrozo
1.2M
875105359001
10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
jharwinbarrozo
1.2M
CTL1206FYW1T
Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlink
jharwinbarrozo
1.1M

Project Name

Worthwhile Green Speeder Bike

Description

USB-Powered ESP32-C5 Indoor Air Quality Monitor with STCC4 CO2/SHT41 (I2C), PMS7003 (UART), AP2112K 3.3V LDO, Polyfuse Protection on 55×45 mm 2-Layer PCB

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor	Qty 1

Controls

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