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I am in the process of designing a fancy USB type c cable (paracord, colourful heat-shrink, coils etc) And I'm worried about resistor values, I don't want to blow my phones port or the charger.

I would like to create a usb 2.0 cable and I think to allow it to be used for fast charging + data I will have to add a 56k pulldown resistor on the D+ and D- lines. is this correct? Does this resistor get added on both sides of the cable, totalling 4 resistors in the cable? Can someone help me with a schematic?

These are the connectors I will be using, one on each end of the cable

With these will I have to remove the resistor from one side?

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    \$\begingroup\$ Is this a phone charger you are trying to make? Where did you get the value of a 56k pulldown? What research have you don into this? If you are trying to build a charger, using D+ and D- lines to control charge rate, then this is a common question we get here, a bit of searching will give you some answers, plus there is loads of information out there about it. This should be a pretty simple task to research, rather than asking us to design it for you. Unless I misread and you are attempting something different? \$\endgroup\$
    – MCG
    Aug 10, 2018 at 14:58
  • \$\begingroup\$ No, just building a cable. Ive looked around but I can find nothing on the cable itself. And the information Ive found on places like mauser/here has been mostly based on building charging systems. \$\endgroup\$ Aug 10, 2018 at 15:17
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    \$\begingroup\$ why would a cable need pulldown resistors? .... i think that you need to do more research \$\endgroup\$
    – jsotola
    Aug 10, 2018 at 15:33
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    \$\begingroup\$ The cable itself doesn't have resistors.... You do need to do a little more research \$\endgroup\$
    – MCG
    Aug 10, 2018 at 16:14
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    \$\begingroup\$ No. Again, it's not the actual cable that has the resistors on it. That answer innyour link does explain the 56k pull ups. But they would be on a PCB on either end of the comms. The answrr mentions the receptacles they go in to get the USB C - USB A connectivity. So yes, you do need more research in general electronics if you still Think the cable itself has pull ups. Are you trying to make a USB C to USB A cable? That was the main reason to be specific for those 56k resistors \$\endgroup\$
    – MCG
    Aug 10, 2018 at 16:25

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To begin, a Type-C to Type-C cable doesn't have any resistors. For C-C connections the corresponding gender-defining pull-up and pull-down resistors are placed inside corresponding ports, and CC line just communicates/connects them across the link. The resistors are needed on Type-C end only for "legacy cables", where the other end is legacy Type-A or Type-B. In no case there are resistors on D+ or D- cable lines; again, these "charger signatures" are properties of charger ports.

The cable specifications are freely available on USB.ORG website, in developer/documentation area, as part of one big zip file USB 3.2 package. Some places have re-posted the individual Type-C Specifications.

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