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USB Power Delivery is able to work over USB Type A/B cables which are specifically designed to support it.

Since the USB Type C was designed much later, I am curious: Do all USB Type C cables support USB PD by default? And do they support a certain level, or the full 100 W?

Related: Does USB Power Delivery handle USB cables that are not PD-aware?

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Yes they are assuming they are certified by the USB group. It is noted in the USB PD 1.0 presentation that it is "compatible with USB 2.0 and 3.0 cables" so they should be fine. The USB-PD spec confirms they are compatible assuming they are spec-compliant. enter image description here

The USB Type-C mechanical/electrical standard dictates the connector and the physical pinout of the connector. USB-PD doesn't alter any of that but rather is an extension of the USB Type-C protocol.

What you'll most likely see in the future is microcontrollers coming out with USB Type-C support/engines that may or may not include the USB-PD extension standard.

Give this article a read, it should help out

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    \$\begingroup\$ "Compatible with existing spec compliant USB cables" is the ticket. \$\endgroup\$
    – William Entriken
    Aug 28, 2015 at 22:11
  • \$\begingroup\$ @FullDecent Yes, sorry, I should have noted that after the picture. Thanks for clarifying \$\endgroup\$
    – Funkyguy
    Aug 28, 2015 at 22:13
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    \$\begingroup\$ There are several problems in this answer, firstly your link to the presentation is dead (though archive.org has a copy), secondly if you actually read the whole presentation it's "compatible" in the sense it won't break existing functionality, but to actually use the new power delivery functionality required a special cable. Thirdly it relates to the original power delivery spec for A and B connectors, USB C has it's own variant. \$\endgroup\$
    – Peter Green
    Jul 8, 2019 at 0:36
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Type-C cables must include CC lines, so they all support USB-PD communication. Not all Type-C cables support the full range of power capabilities that USB-PD specifies, however.

The major differentiation is supported current. Passive Type-C cables support up to 3A by default at any USB-PD voltage range (standard voltages for fixed sources are 5V, 12V and 20V). So passive cables can carry up to 15W at 5V, 36W at 12V or 60W at 20V, if the source and sink negotiate an explicit contract for these voltage/current levels.

In order for a USB-PD compliant source to advertise capabilities greater than 3A (or up to the full 5A limit of the spec) the Type-C cable must be an Electronically Marked Cable Assembly (EMCA) and support SOP' packets. It must respond to the "Discover Identity" VDM sequence (USB-PD spec section 6.4.4.3.1) with a cable VDO packet with bits 6..5 set to indicate 5A current handling capability.

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No Not all USB Type-C Cable supports USB PD by default. Electronically marked cable supports USB PD and "may" support upto 100W

A USB Type-C cable which is not electronically marked can support upto 15W.

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  • \$\begingroup\$ that sounds to me as "yes they do" but if they are not marked then they are limited to 15W \$\endgroup\$
    – arana
    Mar 30, 2020 at 20:51

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