Table of Contents

The Result

As this project is still a work in progress, I’m still waiting for the result :).

Check below for a render:



The Parts

The downloads/parts are listed below. If you look at the PCB on https://aisler.net/p/MXBBWTEF you have the convenient option to also order all the parts. Or you can try to get them via the searches below.

Amount Part Type Datasheet Links
1 USB LiPo Light Rev3  PCB   💾 🛒aisler.net
1 MCP73831 U 🔎 google 🔎 aliexpress
1 MCP1700 3.3V U 🔎 google 🔎 aliexpress
1 D1 SMD LED 1206 D   🔎 aliexpress
1 D2 SMD LED 5730  D    🔎 aliexpress
1  Switch  SW   🔎 aliexpress
2 JST XH J   🔎 aliexpress
2 4.7u C   🔎 aliexpress
2 1u C   🔎 aliexpress
1 470 R   🔎 aliexpress
1 10k R   🔎 aliexpress

The Schematics

My main motivation was, that I wanted to design a PCB that could be plugged straight into the USB port of your computer / charger, without using a cable or usb connector on the PCB.

First, I designed a simple symbol to represent the USB connection.
This is the charger circuit according to the datasheet of the MCP73831.
This is the power circuit, using the design from the datasheet of the MCP1700.

I added a switch, a LED and a Lipo + 3V3 out connector.
To the left you see everything in one picture.

The PCB

I followed the discussion on this thread: https://forum.kicad.info/t/standard-github-usb-trace-on-pcb-footprint-available/1800 to find a USB A plug footprint. I imported it into my local library and assigned it to the USB A Plug symbol.
The view of the PCB in Kicad. I tried to be as symmetrical and organized as possible to simplify soldering, i.e. sort by value and same orientation of diodes.
I uploaded the PCB to https://aisler.net/p/MXBBWTEF to review it and order it.

The 3D Print

This is a TODO, and is waiting for the PCB / soldering.