2-cell PSU added to control board

I added a two cell battery charger, monitor, and protector section to the board. It is rather packed, coming in at around 15mmx45mm for the PSU, and stuffed with components.

I also have done some general cleanup work, such as removing the voltage divider connected to the ESP32, and fixing the footprint for the shift register.

Full Changelog: v0.3.0...v0.4.0
On motor Driver Gerbers.zip
On motor Driver Centroid.zip
ESP32-S3 control board Gerbers.zip
ESP32-S3 control board Centroid.zip
MA735 encoder Gerbers.zip

On-motor driver PCB

In this release, the driver board has been migrated to mount directly on the motor base. It is 11 mm in diameter! Heat may be an issue, but it saves a ton of space on the main board.

Full Changelog: v0.2.0...v0.3.0

v0.2.0

Changes made in this release:

• Switched to an ESP32-S3 processor, involving a lot of tricky routing
• Fixed driver enable issues
• Switched to a flex pcb magnetic encoder with the cable integrated

I have not physically tested this board, and there are no guarantees that this works. This version likely has many issues. I am not going to address issues on this version, because I am moving to a new architecture with components split into separate boards.

Full Changelog: v0.1.0...v0.2.0

v0.1.0

First version of the motor control board. This has an STM32G070CB mcu, TI BQ25060 battery charger, and a TI DRV8311 driver all on a single motor board. There are several design errors with this: the driver does not enable itself using its own supply and needs an external 3.3v supply to start up; the driver lowside pins were not tied to 3.3v causing the channels to be disabled; the Mosi and Miso silkscreen text are swapped; and I chose the wrong power mosfet size.

(a lot of the initial work was done before tracking with git)
Partial Changelog: https://github.com/techy-robot/Mighty-Micro-Motors/commits/v0.1.0