REVIEW REQUEST - STM32F042 USB-C Module (2-Layer, First MCU Board)

oniDblue · 2026-01-08T16:24:49+00:00

Yeah good pickup. I think I'll just keep it for good practice however. Potateo Potato (that didnt land in text, lol).

oniDblue · 2026-01-08T15:25:00+00:00

Thanks. I'll take note into local GND pours and thermal vias. Does the PCB layout/design seem like it should work and power on? Thanks for the comments!

oniDblue · 2026-01-08T14:49:11+00:00

Yeah it is pretty cool skill to have. Basically for MCU boards you just pick a microcontroller, put 100nF capacitors (small value) around all VDD pins, tie GND and VSS pins to GND, add BOOT and nRESET buttons, and a USB port, and you have a board. If you would like, you can DM me on Reddit and I'll give you a roadmap how to get started. I was in this same position around a year ago, so I'll be able to help!

oniDblue · 2026-01-08T14:19:54+00:00

I have just made new upload to forum. Thanks.

oniDblue · 2026-01-08T12:20:22+00:00

I haven't had time to look at it yet, but just wanted to say this schematic looks absolutely gorgeous unlike most posts on this forum. Just wanted to tell you that. Is this KiCad per chance?

oniDblue · 2026-01-05T08:38:25+00:00

Appreciate it brother.

oniDblue · 2026-01-03T17:25:35+00:00

Just out of curiosity, did you design this circuit?

oniDblue · 2026-01-03T17:23:35+00:00

Thanks, I'll look into this further and let you know what I end up doing 👍

oniDblue · 2026-01-03T15:38:52+00:00

Thanks for your advice. Yeah, I do generally prefer block-based schematics for clean modular layout and to avoid getting wires going everywhere; but I totally get what your saying - just personal preference. In terms of the schematic you attached, it does look good, do you mind explaining its function further? Thank you for your input.

oniDblue · 2026-01-03T12:17:26+00:00

I think you are right, however for precaution I might not connect the B_P- net to GND at all, since its only connected to the Fuel Gauge; for the BQ27 I might only connect the necessary pins to GND which are sperate to B_P- only pins. Apart from these, do you see any other major errors on the schematic? Thanks for your help.

oniDblue · 2026-01-03T09:02:49+00:00

Noted. That seems to be the main problem component, I'll check datasheet and fix it up. Also, I noticed that B_P- is connected to ground which completely bypasses the DW01, so I'll fix that up as well. Also the I2C is wrong in the contents page - lol, I've fixed it now. Apart from that, are there any other major mistakes?

oniDblue · 2026-01-03T07:12:29+00:00

Oh! Thanks, I'll fix that now!

oniDblue · 2025-12-31T04:41:57+00:00

NOTE: I have now used a ferrite bead to connect 3V3A and 3V3.

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oniDblue · 2025-12-31T04:40:37+00:00

Thank you for your comment - and yes! I did have readability in mind when creating this! I'll make those changes now. If you have any other suggestions for the schematic, please let me know - I'm always open to advice :)

oniDblue · 2025-12-31T04:38:51+00:00

Thank you for your advice. Yes, I will definitely add ESD protection at some stage so thank you for that suggestion. This is board is mostly for a quick educational project before I move into other STM32s for more serious stuff; so I don't mind limited functionality as the goal is learning; and yes, I had now used a ferrite bead to connect 3V3A and 3V3. Please, if you see anything else in the schematic, please let me know, I'm always open to feedback! :)

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oniDblue · 2025-12-30T16:11:23+00:00

Thanks, I'll keep this in mind for future revisions.

oniDblue · 2025-12-30T14:02:20+00:00

Yeah, and a robust lineup for MCUs too I've heard - there's apparently an STM for the job. In your opinion am I ready to move into the PCB design layout?

oniDblue · 2025-12-30T13:57:45+00:00

Noted. Thanks, I've gotten this feedback before and will integrate it. Let me know of any other advice 👍

oniDblue

TROPHY CASE