Design a compact USB-powered desktop CO₂ air quality monitor device.
Requirements:
Use an accurate NDIR CO₂ sensor module or IC suitable for indoor air monitoring
Use a microcontroller to read the CO₂ sensor and drive a small display
Display real-time CO₂ concentration in ppm on a small OLED or LCD
Include a visual air-quality indication for good / moderate / poor levels, either using RGB/status LEDs or on-screen indicators
Powered from standard USB 5 V for desktop use
Compact form factor suitable for sitting on a desk
Make reasonable engineering choices for the sensor, microcontroller, display, power regulation, connectors, and indicators. Prioritize reliable measurements, readily available components, and a clean intermediate-level design rather than the absolute lowest cost.
Complete and verify the schematic first, including required power regulation, decoupling, programming/debug access, and any sensor/display pull-ups or level shifting.
I’m blocked because execution credits are exhausted, so I can’t modify or inspect the Flux project in this session.
No schematic work has been performed yet: the project is still empty with 0 components and 0 nets. The next step, once execution is available, is to create and verify the schematic for a compact USB-powered CO₂ monitor, likely using:
USB-C 5 V input with protection and 5.1 kΩ CC pull-downs
3.3 V regulation sized from a real power budget
NDIR CO₂ sensor module suitable for indoor monitoring
MCU with programming/debug header
Small I²C OLED display
RGB/status LED indication
Required decoupling, pull-ups, and connectors
Before layout, the schematic should be fully wired, checked against datasheets, and reviewed until there are zero unresolved ERC violations.
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
General Purpose Thick Film Standard Power
and High-Power Chip Resistor
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film
Features:
- RMCF – standard power ratings
- RMCP – high power ratings
- Nickel barrier terminations standard
- Power derating from 100% at 70ºC to zero at +155ºC
- RoHS compliant, REACH compliant, and halogen free
- AEC-Q200 compliant