How to make a custom ultra low profile USB connector.
I found myself in the need of a really low profile USB plug for my new raspberry pi case. There is only a few mm of clearance between the front flap and the USB port and I wanted a permanent WiFi connection. So here is how I did it.
You will need:
- Some strip board (tiny amount)
- USB extension or USB OTG cable to butcher.
- Soldering Iron and Solder
- Helping hands are useful but not
- Some old sim card plastic or simulate thickness packing (non conductive)
Step 1: Make the Connector.
Offer up the strip board to a normal USB and make sure the tracks match the contact pins width. My tracks are 2mm wide with a 0.4mm gap.
With a knife cut a 4 row strip just inside the the next two strips. So you should end up with 4 contact strips and some spare non conductive material either side.
Cut the strip just the right size to fit all the way into the USB port with only 1 row of holes barely showing.
Use a file to tidy all the edges and adjust as required. You might need to use a knife to remove any unwanted copper.
Step 2: Get the Socket Ready.
Take your USB extension/ OTG cable and cut of the plug end retaining the socket and cable.
Strip back the insulation to reveal as much wire as suits your need. You can safely remove the outer shielding wires.
You should be left with socket with 4 wires (red, black, green and white)
Strip the end of these wires a tiny amount.
Step 3: Solder
Using helping hands set the copper strips facing upwards.
On the edge that you have picked for the outside feed the strip wires up from underneath and Solder left to right. Red, White, Green, Black which are pins 1-4 respectively.
Step 4: Finish
Once soldered you may need to file the Solder down a bit.
Then add some glue to the connections to strengthen and insulate them.
I found with some of my USB ports but not all the strip board was not thick enough to make a good contact.
To solve this cut a small square of SIM card plastic and glue to the bottom of the connector. This makes the whole thing the perfect thickness.
Enjoy your new low profile connector/extension.