USBc Footprint connection weirdness in a PCB design

I hereby certify that I am not simply asking someone else to design a footprint for me.

This is an auto-generated message that is in place on the “footprints” section of the KiCad.info forum. If I remove it and ask for a footprint to be designed anyway, I understand that I will be subject to forum members telling me to go design my own footprint or referring me to a 3rd party footprint site.

Hi, I am trying to build a PCB with USB typeC connector and I am going to use this: HC-TYPE-C-16P-01A | HCTL | Price | In Stock | LCSC Electronics .In the KiCad there is a footprint called: Connector_USB:USB_C_Receptacle_HCTL_HC-TYPE-C-16P-01A which I believe it should be the correct one but in the PCB Editor it has multiple pins for same connection as in the picture below ;

For example the first two pins (A12-B9) and last two pins (A9-A12) have multiple pins when I click on them it shows two different pins as in the screenshot. Is this normal? Also should I connect pins B9 and A9 (5V pins) in the PCB editor as well or they both supply 5V separately ? Also for the two different D+D- should I connect them or they are already connected?

Yes, this is quite normal.
With USB-C connectors, the pins have specific names (A1 through A12 and B1 though B12) and these have specific defined meanings. Because the connector is reversible, it’s also symmetric and with quite a lot of double or even quadrupled pins.
The connector fabricator knows this of course, and not all pins in the connector have separate pads on the PCB, and multiple pins end up on the same pad.

The footprint is indeed odd. It seems to be laid out so you can mount the connector on either side of the PCB.

That’s why I have two drawers for SMD resistors and caps. One for front mounting and one for back mounting. :slight_smile:
Sorry, I could not resist! Albeit I understood what you wanted to say. It’s a property of USB-C, the plug is reversible. And it is easier to make the connections on the PCB.

To the OP: You are aware that USB has requirements for impedance and length matching on the PCB? I doubt your layout did consider that.

Trust but VERIFY! :wink:

The page you link too has the recommended layout in the data sheet.

IF you blow it up large enough you will see this starting to make sense. I think…

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Do I need to connect them in the PCB editor as well ? Especially for the duplicate 5V and duplicate D+ D-. Or they are internally connected without routing?

Do I need to connect them in the PCB editor as well ? Especially for the duplicate 5V and duplicate D+ D-. Or they are internally connected without routing?

What you mean by impedance and length matching ?

This Forum is here to help with KiCad specific queries/issues not general electronics help. If you are designing with USB you need to know this stuff, Google will help you, do some research.

But you know this already . . .

This is clear, I know what USB-C is, thank you very much . But it’s the first time I’ve seen a PCB footprint like this, and honestly, I think it causes more problems than simply having two footprints: top and bottom.
But then, I’m simple…

Two resistors in a trash can had a chat.
– Why did you end up here?
– My EE didn’t like daddy jokes. But I couldn’t resist.

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I did my first project with USB last month. While researching the requirements I came across a wise comment:

  • USB low speed: Don’t worry too much about it.
  • USB full speed: Try to keep the lengths the same
  • USB high speed: Length matching and impedance are critical
  • USB 3 and above: Why do you hate yourself? Get counseling!
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