• Boards Ordered

    leo60228 • 01/03/2022 at 00:55 • 0 comments

    I ordered the boards. I should get them in a few weeks. Maybe I should have done this before I took a few weeks off the project due to the holidays...

  • Routing, again

    leo60228 • 12/24/2021 at 00:48 • 0 comments

    I decided to redo the routing. I think this time it came out quite a bit nicer.

  • PCB Routed

    leo60228 • 12/22/2021 at 06:44 • 0 comments

    Routing this was a massive pain. There was definitely a reason the original had double sided assembly. I also didn't do an especially great job...

    It looks nice from the front, though:
    https://vriska.club/i/0vbmz.webp

  • Footprints Assigned

    leo60228 • 12/22/2021 at 04:45 • 0 comments

    I've assigned footprints to all the components. For passives, I mostly used 0402, with the voltage divider using 0604 due to JLCPCB not having an 0402 13kΩ resistor in their basic parts, and the sense resistors being 1206 as advised in the datasheet. Now to route the PCB...

    unrouted PCB with components

  • Sense resistor and current scaling

    leo60228 • 12/22/2021 at 04:15 • 0 comments

    I switched the current sense resistor to 100mΩ for better availability. However, this also increased the RMS current above the maximum of 1.4A. As I plan to fine-tune current scaling in software, I didn't need the Vref potentiometer, so I replaced it with a fixed 13k resistor for a maximum current of: (Wolfram Alpha)

  • KiCAD Conversion

    leo60228 • 12/22/2021 at 02:40 • 0 comments

    Watterott's design files are for Eagle, while I normally work in KiCAD. KiCAD has perfectly workable importers for Eagle schematics and PCBs, with the minor quirk that you have to start eeschema and pcbnew directly (instead of via the main KiCAD application) for the import option to appear. However, updating the PCB from the schematic failed. I didn't spend much time investigating this, as I planned to redo the routing anyway.

    The resulting board still looked like an Eagle schematic and used Eagle symbols, which isn't great. Luckily, this was easy enough to manually fix, though a bit tedious. One annoying issue was that most symbols from KiCAD libraries were oriented 90° off from their Eagle counterparts.

    The original schematic contains a symbol for a solder jumper. I left this untouched (to the annoyance of the ERC) as I plan to remove that jumper in my final schematic anyway.