Oak

V1.0

🌳 Outdoor LoRa-GPS tracker with E-Ink display 🔑

power 18650
wireless LoRa
sensor GPS, E-Ink
mcu SAMD21G18
bom items 82
bom cost USD $78.93
vendors 6
status ongoing

Lessons learnt

Good practices to continue for future projects

  • Add functional logical blocks in schematic to use similar circuits in future versions or other projects
  • Use stencil SMD soldering with SMD components as alternatives wherever possible
  • Use minimum number of through-hole components
  • Check Gerber file format with the PCB manufacturer before rendering them
  • Check `F.Paste` and `B.Paste` layers for SMD stencil pattern

V2.0

For next iteration

  • Use SMD components only on top layer for one-step manual SMD stencil soldering process
  • Place a writable area on the silkscreen to note down LoRa node address or other associated numbers
  • Add a PCB-edge through hole test point for GND so that it can be always left connected and accessed for both top and bottom layer probe testing
  • Use a smaller SSD1306 I2C OLED display instead of E-Ink

Board bring-up

  • Check with 2 PCBs to conclude whether it is a design issue or a soldering / manufacturing / assembly issue
  • Power it with USB only. Check `GND` and `VBUS` is `5V`. Check `GND` and `3.3V` is `3.3V`
  • Bridge the open solder jumper for `3.3V`

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Project Attributes
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LoRa

LoRa Antenna

GPS

E-Ink

Firmware

SPI

Manufacturing

Schedule

The Gantt Chart below indicates the actual time taken to complete this project. It can be used as a rough guidline when duplicating or iterating similar projects in the future.