Mike Rankin created this tiny sensor board with an ARM Cortex M0+ microcontroller and OLED display:
0miker0’s Blog: SAMD21G Sensor Board
It’s pretty tiny so a 4 layer board made the whole job easier. The top and bottom are pretty much dedicated for components, layer1 are tracks and power traces, layer2 is a ground plane. Mixing up an internal plane and routing layer was interesting.
The hardware consists of:
- SAMD21G18A processor (used in the Adafruit Feather)
- HDC1080DMBT temperature/humidity sensor
- ADXL345B accelerometer
- DS1340U RTC
- MCP73833 LiPo battery charger
- MicroSD card connector
- Navigation Button and pushbutton
- 0.66″ mono oled display
- Micro USB connector for charging and uploading new sketches
The design files and source code are available on GitHub:
For more detail: Atmel SAMD21G Sensor Board