2 layers76.3 × 54.8 mm
Project 1
AJ-returns/PCB
It includes the my designs of already existing as well as my own original PCB designs.
21 parts
2 layers78 × 84 mm
It includes the my designs of already existing as well as my own original PCB designs.
- Size
- 78 × 84 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 8
- Nets
- 39
- Pads
- 67
- Tracks, vias
- 72, 0
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 10.0 (file 20260206)
- Created
- 10 Aug 2026
- Updated
- 10 Aug 2026
Overview
AQI is an open-source printed circuit board by AJ-returns, from the AJ-returns/PCB repository on GitHub. It is a 2-layer board of 78 × 84 mm with 8 parts on 39 nets, routed with 72 tracks and 0 vias.
It is built around the DHT22. Its parts include 3 resistors and 2 ICs.
Main components
1Parts
8| Qty | Value | Footprint | References |
|---|---|---|---|
| 1 | 100k | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R1 |
| 1 | 10k | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R2 |
| 1 | 200k | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R3 |
| 1 | DHT22 | Connector_PinHeader_2.54mm:PinHeader_1x04_P2.54mm_Vertical | DHT22 |
| 1 | LCD-016N002L | LCD-16X2:MODULE_LCD-16X2 | U2 |
| 1 | MQ135 | Connector_PinHeader_2.54mm:PinHeader_1x04_P2.54mm_Vertical | MQ135 |
| 1 | R_Potentiometer | Potentiometer_THT:Potentiometer_Alps_RK163_Single_Horizontal | RV1 |
| 1 | ~ | ESP32_Footprints:ESP32_30pin | U1 |
Questions
How big is the AQI PCB?
It measures 78 × 84 mm and has 2 copper layers, 1.6 mm thick.
What parts does the AQI use?
8 parts, built around the DHT22. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the AQI KiCad files?
From the AJ-returns/PCB repository on GitHub, at the commit this page was made from: the board is AQI/.history/AQI.kicad_pcb and its schematic AQI/.history/AQI.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the AQI design in my own project?
Its repository states no licence, so its author keeps all rights: ask AJ-returns before reusing the design.
More from AJ-returns/PCB
2- 2 layers
Project 2
AJ-returns/PCB
It includes the my designs of already existing as well as my own original PCB designs.
10 parts
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