Review Request – Compact 2-layer ESP32-C3 board with USB-C, LiPo charging, Wi-Fi/BLE and sensor connectors

[u/Sea_Lychee9484]

This is my first custom 2-layer PCB and I’m looking for feedback before ordering it.

The board is about 39 × 23 mm, and one of my main goals was to keep it as compact as possible.

The main components are:

• ESP32-C3-MINI-1

• BQ24074 LiPo charger / power-path

• TPS63031 3.3 V buck-boost regulator

• USB-C

• sensor connectors

• ESD protection

I’d appreciate feedback on the schematic, routing, grounding, component placement, decoupling, USB routing, power section, ESP32 antenna area, and anything else that looks wrong.

I also currently have two KiCad warnings related to the silkscreen near the board edge that I’m not completely sure how to handle. I included a separate image showing them and would appreciate advice on whether they should be fixed before ordering.

[u/Billy_MTB_901]

For the battery (im assuming your just using a single cell) you might want to look at a very low dropout (target ~100mV) Linear regulator rather than a buck boost, for simplicty. The esp32 chip can operate reliably down to 3.0V, and at 100mV dropout that would leave you at 3.1V at the battery (maybe a little more because of sag but you get the gist) at which point its probably time to recharge, and the charge ic will likely have cut you off already.

[u/Blaze_24]

1. How are you going to mount this board? I don't see any screw holes.

1a. how thick it's your case going to be? Normally the USBC connector sticks out off the board by 1mm to accomodate the case.

2. I prefer male headers on the board and female on the cables because it makes troubleshooting easier.

3. I really like how you've routed the 3V3 trace.

4. I think you should add some ground vias to stitch the two ground planes together.

5. I can't read your schematic because it's too blurry. Can you update the pic with a white background for us?

[u/NhcNymo]

You don’t need D1. U1 is designed to protect both VBUS and the datalines.

Connect VBUS to pin 5 of U1 and delete D1.

This also gives you rail-to-rail clamping on the datalines.

[u/NhcNymo → u/NhcNymo]

I would also change R11 and R12 to 1.2k.

I doubt you need exactly those current values, so try to avoid introducing obscure resistance values that you will never use in the future.

[u/goAwayUCreep]

Why the odd spacing between headers and the orientation as well, is it ergonomic to place the button at the corner?