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Early editions of RPi 4 had hardware design issues in the USB-C port. (Ref: 1) Since then an updated board has been issued. However the official schematics still show the old USB-C Power In circuit (i.e., with CC1 and CC2 shorted and pulled down by a single 5K1 resistor).

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Are updated schematics available for the updated USB-C Power In?

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    You said it yourself: the official schematics are not yet updated. You could write a letter to the Pi foundation, if enough users nag them about this, they will probably do it. Jun 14 '21 at 6:26
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    Thanks @DmitryGrigoryev, yes I know it was a stretch but I was hoping someone might know another source. Maybe I can suggest to readers to upvote this question as a form of nagging?
    – RowanP
    Jun 14 '21 at 9:39
  • FWIW I measure the unpowered resistance between CC1 and CC2 on my newer model Pi as 10.24Kohm. So good bet they’re now independently pulled down by 5.1Kohm.
    – RowanP
    Jun 14 '21 at 9:46
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    Nagging here wouldn't work for sure. Even writing to the foundation is not guaranteed to work: people have been asking them to release more complete schematics for years and we still don't have those. Arguably though, in this case it's not just laziness, the fear of cheap clones appearing also plays a role, though I don't think the fear is founded. Broadcom is well-known not to sell their ICs to random people on the streets. Jun 14 '21 at 12:03
  • @DmitryGrigoryev: You're correct - nagging here won't help an iota. And it's unlikely St. Jude will intervene, but this might be one way to push for a lost cause. :)
    – Seamus
    Jun 20 '21 at 19:47
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There is truth in @DmitryGrigoryev comment. However, on the Raspberry Pi GitHub site, there is an opportunity to file an Issue or a Bug Report.

In this case, it seems the Documentation repo would be the place to go. If you're not familiar with the GitHub interface, you are looking for the "Issues" tab at the top of the page. Clicking it will take you to a filter-able listing of issues filed, and from there, clicking the New Issue button will take you to a form for submitting your issue.

In some cases (typically bug reports), you'll be asked to follow a format for entering your Issue - in other cases, it's a simple free-form input - a slight re-wording of your question here would likely be fine.

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  • Created bug report as suggested github.com/raspberrypi/documentation/issues/1915
    – RowanP
    Jun 17 '21 at 6:10
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    It only took a couple of hours to get a non-committal answer that, “ Schematics will be moved outside of the documentation repo during the reorganisation, see #1911. We may look at this then” … and the issue was closed.
    – RowanP
    Jun 17 '21 at 11:45
  • @RowanP: Yes - well - as a group they impress me as being rather independent - even arbitrary at times. I'll stop there...
    – Seamus
    Jun 17 '21 at 14:59
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    @RowanP: Don't know if you're following the issue you created (#1915), but the answer now seems to be, "don't hold your breath" waiting for a revision.
    – Seamus
    Jun 21 '21 at 9:09
  • Hackaday have published a story on the conversation. hackaday.com/2021/06/23/…
    – RowanP
    Jun 23 '21 at 8:35

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