Type-C "configuration resistors" replace "termination resistors"?

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Hi! question, I'd like to use a USB-C receptable on my PCB (with a Atmega32U4), and it ought to be connected to an ancient legacy USB-A-V2.0 host port on the PC. Do I still need termination resistors on D- and D+, or are they now obsolete using USB type-C? I know that USB type C wants those 5.1K pull downs on CC1 and CC2, called "configuration resistors". But I'm not sure if they replace the former 22R termination resistors on the data lines, or not?

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Last Edited: Mon. Nov 5, 2018 - 08:43 AM
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Termination resistors are an electrical requirement and are still necessary.

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Thanks Kartman!

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O.T.

Krümelmonster wrote:
I'd like to use a USB-C receptable on my PCB ...
My experience with USB Type-C is the connectors will de-mate with wear.

If can spare the space then USB type A or B in high-retention else micro B.

Kycon - Products - USB (search for retention)

 

"Dare to be naïve." - Buckminster Fuller

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On my next PCB I plan on not using any of the USB style connectors.  Maybe the C is okay. I've never seen one.  But the others are way too long and make it easy to rip off the board connector.   I will use either a 2mm or 0.050 header on the board with a mating squeeze on connector on the cable.

 

Here is a picture of a cable from my Atmel ICE connecting to my board.  I used a 2mm header on this because this board was built before I got an Atmel ICE, which uses 0.050 connectors.

 

Notice the 2mm 6 pin header has 2 missing pins.  Not missing actually, they are plugged into the corresponding female connectors on the squeeze on the unplugged connector seen above the header.  This makes is much more difficult to plug it in incorrectly.

 

The wires in the ribbon cable from the ICE don't match up with the header either.  That's okay.  It's easy to squeeze on one wire at a time.  Just get an extra squeezer and cut the latching hooks off the end.  You can even put on a strain relief afterwards.  I know 3M makes 'em.