Alternate USB connector for ProMicro

I wonder if I can add an alternate USB connector for the ProMicro.

The ProMicro has an built-in micro-usb connector but it’s a bit fragile (the connector might came off with the cable when I unplugged it)

I want to add an alternate mini-usb connector, I would need: VCC, GND, D+, D-
I can see the VCC and GND on the ProMicro but I have no idea how I should connect D+ and D-

EDIT: the mini-usb will be soldered to my PCB and the ProMicro will be the controller board for it.

I plan to use QMK firmware to add keymap the ProMicro.

Thank you for reading!

The Pro Micro is a creation of SparkFun Electronics, being an Open Source Hardware design. On this page you can find the original Pro Micro for sale (quite more expensive than Chinese clones), as well as the schematics and Eagle files for editing.

BTW, you connect D- to pin 3 and D+ to pin 4 of the ATmega32U4, both using a 22 ohms resistor for current limiting.

There’s a design for a USB-C version of the pro micro that’s intended to be more durable plus all the other advantages of USB-C.

hmm… interesting, though it seems that board is still in development

I have searched around but it seems pin 3 or 4 of the ATmega32U4 in the ProMicro are not accessible from outside

I guess I will use this kind of “detachable cable”

1 Like

Are you brave/adventurous/crazy?

If so, there is this:

1 Like

You could take a look at’s GNAP that has a mini usb soldered to the PCB but breaks out so you can solder in a micro usb cable for the controller

1 Like

@Tom_Kazansky You can use magnetic adapters. It’s a lot cheaper, these detachable cables can get pretty expensive.

I just use magnetic adapters. You can also put a glob of epoxy on the back of the connector, that should secure it.

that’s nice, though I’m not sure I can solder those small parts, my hand shakes too much :frowning:

I see, that probably cheaper than the cable I posted above, thank you!

thank you, I will look into them.

Yeah, I know what you mean. My hands don’t shake, but I don’t have that fine of control, and that would be challenging, at best.