Is the use of USB-C 3.1 in a PCB design restricted? - Page 1
Forum section: electronics / projects

author: alex_eevblog
author_rank: Newbie
timestamp: May 10, 2022, 03:02:47 pm
content: Hi, I would like to use USB C 24 pin male / female connectors to connect different PCBs together.However I am wondering if there are any restriction (not technical but by law) what I can do and what I can not do with USB-C version 3.1 and above?Does the USB-IF limits the usage or are any licenses needed (as it would be with HDMI)?Have a great day!

author: ejeffrey
author_rank: Super Contributor
timestamp: May 10, 2022, 04:00:34 pm
content: You want to use USB on your product or you want to use the USB-C connector for some other purpose?To make a product with USB you will need to get access to a vendor ID/product ID. In addition there are certification requirements and a trademark license fee to use the USB trademarks on your product. I don't think there are per port license fees like HDMI.If you want to buy USB-C connectors from digikey and use them for some other purpose I don't think anyone can stop you but it is generally considered a poor idea. Someone is guaranteed to assume they can plug another USB device and have it do something. At the very least it shouldn't damage anything when someone does that.

author: metrologist
author_rank: Super Contributor
timestamp: May 10, 2022, 04:17:51 pm
content: There are no legal concerns using OTS parts. Just don't publish protected claims or terms.

author: SiliconWizard
author_rank: Super Contributor
timestamp: May 10, 2022, 06:29:02 pm
content: What you can't do is mention "USB" or any of the associated trademarks on your product (such as USB-C, USB Type-C, etc.) and/or claim compliance with them (even worse.) That's what is protected. If you don't, there shouldn't be any IP issues.Now beyond legal IP issues, if said connector was accessible to the user, that may still be a problem: even if it wasn't claimed as USB, users may still try to plug it to some USB device or host, which could potentially destroy stuff if you haven't taken measures against that, or at best confuse users.But if it's strictly internal to some product, this problem won't arise. There might still be a "small" problem of repairability (if that's ever a concern to you), as that may confuse technicians trying to repair the product, but that's probably a minor point, and you could always document that in service manuals. Which leads to small advice: consistant with the first paragraph, avoid mentioning "USB" in any of your service manuals, even if those are just meant as internal documents. To be even more strict, I would avoid using the term "USB" in your BOMs for those connectors, and would just label them some kind of "multipair connector", along with vendor references. Avoid using the protected terms even if in documents not supposed to be read by end users. Just my 2 cents - that might sound a bit much, but if you want to be on the safe side...

author: bson
author_rank: Unknown
timestamp: May 10, 2022, 06:36:37 pm
content: More specifically, you can'tsellproducts using trademarked logos and names without a license to them, which is obtained through the industry forum. You can of course design PCBs with USB interfaces to your heart's content, and even show them to all your friends, coworkers and potential investors. You just can't use the terms in marketing or sales activities. You could, possibly get away with a phrase like "USB 3.1™ compatible" and then note that USB and USB 3.1 are trademarks of the USB Industry Forum. But the legal review and overhead for something sketchy like this is probably more work and expense than simply becoming a member and getting proper certification for the product. Especially since you may find yourself defending the practice in court.

author: alex_eevblog
author_rank: Newbie
timestamp: May 10, 2022, 08:24:24 pm
content: Thank you for all your very informative answers!!!I am using the pins accordingly to the USB C 3.1 usage. This way I lose quite some pins, but there can not happen any short circuit by any misuse. The device would also not draw any power from an host as the CC pins are not connected to a resistor. All pins (except for the 5V and GND pins) are used for 3.3V data transmission and if something different as the desired PCB would be connected, all data lines will immediately be pulled down. From my naive view, this should help to lower the risk of possible damage. I will definetly not use the term USB ;-)

author: metrologist
author_rank: Super Contributor
timestamp: May 10, 2022, 09:30:50 pm
content: You can use USB, that term is not trademarked. Just do not use the USB-IF protected terms.https://www.usb.org/sites/default/files/usb-if_logo_usage_guidelines_final_as_of_november_2_2018_locked_0.pdfUSB and the old trident fork are not protected, but naturally they have classic meaning in practical use.

author: ejeffrey
author_rank: Super Contributor
timestamp: May 11, 2022, 06:32:57 pm
content: Quote from: alex_eevblog on May 10, 2022, 08:24:24 pmLegally that is probably fine as far as the USB-IF is concerned. They would certainly prefer you not to do that, but as far as I understand there isn't much they can do. I believe but am not 100% sure that a USB compliant device needs to be able to tolerate up to 5V continuous on any pin. If that is correct, then from a technical standpoint your device should not damage a compliant USB device.The other area where you might run into legal trouble is consumer protection laws. Even if you don't use the USB trademark logos, if your device is marketed deceptively or causes damage you could be on the hook for liability, but it doesn't sound like that should be an issue for you.As I said, this sort of thing is definitely discouraged in many situations on the grounds of user confusion, but people still do it because it is a hard to beat combination of inexpensive, small footprint, and high performance connector, and widely available.

author: pigrew
author_rank: Frequent Contributor
timestamp: May 11, 2022, 07:03:55 pm
content: ZeroPlus Logic analyzers (e.g. LAP-F1-64) are an example of a product that misuses USB connectors and cables (full size, though, not USB-C) They are in Taiwan, perhaps laws are different there.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: May 11, 2022, 07:08:30 pm
content: The law seems to be convoluted. If you can't use mention USB at all, then a warning sticker saying that this socket is not USB compliant is banned which seems nonsensical.

author: ejeffrey
author_rank: Super Contributor
timestamp: May 11, 2022, 09:34:46 pm
content: Quote from: CatalinaWOW on May 11, 2022, 07:08:30 pmFirst, apparently USB is not itself trademarked, so that point is mostly moot. USB-C, USBC, and USB4 are all trademarks.But also that isn't how trademark law works at all. It's totally fine to use a trademark to refer to the trademarked product. You can certainly say "this device is not USB compliant" You can probably even say "this product is compatible with USB-C devices". USB-C is a trademark of the USB-IF." You just can't use the trademarks to imply that your device is approved of or certified by the USB-IF. Preventing consumer confusion is the main purpose of trademark law, so that tends to be how it is decided. This does mean that even if you say in small print that the device isn't certified, if a "ordinary consumer" looking at your packaging or marketing would likely to be misled by your use of trademarked names, phrases, or logos you are likely violating trademark law.A lot of people think that trademark law prevents all use of a trademark. Mostly this confusion is because the conventional wisdom among advertisers is to avoid using your competitors name. When paper towel commercials show that their product is "2x more absorbent than the leading brand" or whatever, they aren't doing that to avoid trademark infringement, they are doing it because they don't want to provide free advertising for their competitor.

author: Monkeh
author_rank: Super Contributor
timestamp: May 11, 2022, 09:40:48 pm
content: Quote from: ejeffrey on May 11, 2022, 09:34:46 pmOr open themselves to being sued when their claims can then be proven false.