T4.1 External USB C Connector

[vjmuzik]

Here's a quick write up for a permanent and relatively simple way for anyone wanting to add an external USB connector to a Teensy 4.1 based PCB.

First step is to make 2 solder balls on the D+ and D- pads


Next you want to similarly make 2 solder balls on the ends of 2 pins


Take those 2 pins and slide them in position on your PCB without soldering them


Now you can place your Teensy into position and solder it down


Then you have to carefully reach your soldering iron under the Teensy and heat the solder balls together while pushing up on the pins from the bottom


Once you have it soldered to the Teensy you can then solder it to the PCB and cut the pins to size

I made use of this through hole USB 2.0 Type-C connector, but any other one would work fine. I've only tested uploading sketches and Serial communication, so as far as signal integrity goes I haven't had issues yet and my prototype board had some errors in it so I had to use a couple inches of hookup wire between the Teensy and the USB C connector which is definitely not ideal in any way.

 

[luni]

Interesting idea and a nice Type-C connector. If you don't mind I'll steal this idea and try to make a small castellated adapter board to add a USB-C connector to the T4.1. Care to mention which one is D+ in your first picture?

 

[vjmuzik]

As per the schematic D+ is on the ground side and D- is on the power side, I thought about designing a small board, but personally I probably won’t need it so I didn’t.

 

[teensyweensyz]

Do you only need D+ and D- ? What about power/GND? Will this just plug straight into the computer and enumerate the same way the factory USB port does?

 

[vjmuzik]

I had power and ground connected on mine, if you had a different power source then you should only need ground in addition to D+ and D- like any other USB connection. It does enumerate just like normal though, nothing special needs to be done once the connections are made.

 

[teensyweensyz]

Great, and I suspect I should give it VUSB to be safe?

 

[vjmuzik]

If you want it to be bus powered then yeah, otherwise you need an external source.

 

[teensyweensyz]

Can that pad supply 5V into the Teensy (and enumerate the Teensy) from the computer that is connected to the newly soldered USB breakout?

 

[vjmuzik]

Yeah, just like the onboard micro USB.

 

[teensyweensyz]

Thanks! This helped a lot.

 

[devtanc]

I know this is a few years old, but in case anyone wants to do something like this going forward, I have something that may help. As I tried to do this while prototyping I ran into a few times where efforts to swap from one prototype board to another, the data line traces were ripped off the board, leading to an unusable teensy.

I created this board that fits just between the header pins when soldered on, and it uses the anchors for the micro to give a more secure grip, while exposing the underlying pins by soldering through the board holes. If you want to place header pins in the hols, they will fit, and will be held on much more securely than the above solution, though they will need to be trimmed a bit to match the length of the other pins. Either that, or you could use a connector that supports through-hole headers.

I haven't had any issues using this to connect to usbc data lines on another board, and have used it for nearly 30-40 boards. Currently I just solder a set of wires between these pins and the board to give me a bit more flexibility. I ordered this once from JLCPCB and it provides 125 of them, so you only need to order once and you're good for forever, basically.

Hope these help someone!

 

[defragster]

Hope these help someone!

That looks interesting and useful.
Looking at Teensy it is scary how close VUSB pad is to that connector GND tab.

 

[devtanc]

Looking at Teensy it is scary how close VUSB pad is to that connector GND tab.

Yeah, that's true. I haven't had any of the ones I've soldered short, but it's definitely close.