Nano Hub

Created by [Irtaza] • Started on June 11, 2025

A custom tiny USB hub for iPad/mobile!

June 11th: Started working on the schematic!

Opened up KiCAD and, after looking through some online references, like the onboard guide, started to place components. KiCAD Schematic)

However, I soon realised that: 1. KiCAD does not have all the components that I would require in its library, and 2. Also, the board would require PCBA,

So instead, I shifted to EasyEDA.

I added all the components that best fit my requirements and started wiring them, but when trying to rotate one component, I accidentally reloaded the page, so all progress was lost (learned that EasyEDA does not auto save your work the hard way) :(

Now I am downloading the desktop app and will continue with the schematic tomorrow!

Time spent: 2 hours

June 13th: Almost finished the schematic!

Decided to move away from EasyEDA because all of the UI and the keyboard shortcuts were different, and I couldn't get the hang of them. So I opened up KiCAD again and started the schematic from scratch. I used the 16-pin USB C ports schematic and, after some research between FE1.1s and SL2.1A, chose FE1.1s as the USB 2.0 hub controller!

I opened up the FE1.1s datasheet and then routed each pin to where it specified. I left the config and LED pins alone for now, and will get to them later on after researching more about what they are supposed to do!

And I also routed the power pins on the hub and ports with 10uF capacitors to ground and the CC pins on the USB-C ports through 5.1kΩ resistors to ground.

KiCAD Schematic

Time spent: 1.5 hours

June 14th: Finished the ports part of the schematic!

Looked at lots of USB-C hubs schematics and used them as a reference to modify my own! - Powered each of the ports with direct 5V from the upstream USB-C. - Added 2 decoupling capacitors on the 5V. - Added a crystal. - Routed the config pins using those schematics!

Also edited the resistor and capacitor values to show their actual values (e.g., 10k or 10uF) instead of Resistor.

And routed the shields to ground.

image

Time spent: 1 hour