When I designed the first PCB, I didn't really consider the ease with which they could be assembled. This was quite annoying as I would have to hand solder one side (as I could not reflow the other side). This and the idea that I wanted a rechargeable RTC battery made me design a new version.

In this version I reduced the amount of layers from 4 to 2, moved most of the components to a single side, I added a rechargable 5.5mAh RTC battery (should have a battery life of around 6 months without charging), circuit to charge the RTC battery and I added more buttons to allow switching between profiles. The Kicad design files can be found at: https://github.com/itzandroidtab/totp/tree/master/hardware/kicad

PCB back with components

PCB front with components

During this time I also created a case in Inventor. The case is held together using 4x M1.4 and is specificly designed to keep the movement of the PCB as low as possible. Exported STL files can be found at: https://github.com/itzandroidtab/totp/tree/master/hardware/case