KiCAD design files

[cyber-murmel]

Hello, I wanted to view the new schematic source files. The problem is that I have no windows machine that didn't let altium crash. I used the existing schematic pdf and the altium to kicad converter to redesign the schematic in kicad. The intent of this exercise was to make the schematic more accessible to people who don't own windows or can't or don't want to run altium.

My plan is to order some PCBs using the original gerber files and some using the kicad design. I would like if a quick sanity check of the kicad files was possible.

Hope people find this work helpful :-)

[cyber-murmel]

I also still need to do some silk screen cleanup and pad resizing.

[coon42]

I also had this plan but didn't find time for it yet. Please keep doing it! :)

[lucysrausch]

Hey,

I appreciate your efforts to revive this project. However I want to note a few things to prevent disappointments:

OtterControl is a properly working motor controller and it works as it is. However, after >1 year experience it seems like this is not the most reliable controller. It does not spontaneously go up in flames, but it could be more resistant.

Concretely, if I would do a spin-off of this controller (based on stmbl running on a STM32F303) I would change the following things:

• Use IR2102 gate drivers instead of the MIC4605. The MICs are fine, however when they blow up because of a mosfet failure, they tend to short the VBUS rail to the signal inputs which reliably kills the STM32 and every other semiconductor on the board.

• Use TO220 packaged Fets instead of DPAK. TO220 is easier to cool, and more important, easier to replace.

• Use a Flyback topology instead of the XL7015. The XL7015 works fine, however it is not short-circuit proof and misbehaves when overloaded. As most buck-converters, this chip fails by shorting the main switching transistor, applying VBUS to the input of the ACT4088 which also kills every single semiconductor of the board. A flyback topology with a dedicated transformer would improve this behavior.

• The current shunt topology is suboptimal as the routing adds traces of different length that add resistance to the shunt values. For the 3mOhm option, this is not too big of a problem, but with the 1mOhm shunts there is a significant difference between the very left and the very right phase current (almost by a factor of 2). Unfortunately, a more sophisticated layout would require a complete redesign and probably a different formfactor.

This being said, please don't expect too much. OtterControl works, but it could be improved.

Best, Niklas

[cyber-murmel]

Use IR2102 gate drivers instead of the MIC4605.

:+1:

Use TO220 packaged Fets instead of DPAK.

I think doing a hybrid footprint is possible.

Use a Flyback topology instead of the XL7015.

I don't have really much experience designing power supply regulator circuits. If there is an implementable reference design, that would be nice. For now I would stick to the buck converter.

The current shunt topology is suboptimal as the routing adds traces of different length that add resistance to the shunt values.

Maybe one can tackle this problem by adding meandering to the traces so that all have the same length.

Would you be interested in a repo where multiple people can work collaboratively on the project or rather have it the way that everyone has their own fork?

[lucysrausch]

Sure, just create your own repo and start adding people^^