USB Type-C Specification 2.1 allows up to 240W Extended Power Range (EPR)

Many devices have switched from a Micro USB port or a power barrel jack to the USB-C port in recent years, as the latter allows for higher currents, and up to 100W power input in USB PD (Power Delivery) compliant systems.

While 100W will be more than enough for most devices, more power-hungry devices or systems still need a power brick, for example, gaming laptops and mobile workstations. But the USB Type-C specification 2.1 aims to change that by upping the maximum power to 240W.

As noted by Benson Leung in a Reddit Thread the part of the specification that handles the 240W power is the EPR (“Extended Power Range”) that defines requirements for cables, chargers, and devices:

3.11 Extended Power Range (EPR) Cables
3.11.1 Electrical Requirements
Extended Power Range cables have additional requirements to assure that these cables can deliver the full defined voltage and current range for USB PD EPR operation. EPR cables shall functionally support a reported 50 V and 5 A o peration. The minimum functional voltage that a cable shall support is 53.65 V. The electrical components potentially in the path of V BUS in an EPR cable, e.g. bypass capacitors, should be minimally rated for 63 V.

To control the impact of inductive kickback and ringing that can increase the chance of arcing between a USB Type-C plug and receptacle when a cable is removed while power is still applied, an EPR cable may include a snubber capacitor within the plug at ea ch end of the cable. See Appendix H for more information.

3.11.2 EPR Cable Identification Requirements
All EPR cables shall be Electronically Marked and include EPR-specific information in the eMarker as defined by the USB PD specification. As defined in the USB PD specification, EPR cables are marked as 50 V and 5 A capable. All EPR cables shall be visibly  identified with EPR cable identification icons as defined by the USB-IF. This is required so that end users will be able to confirm visually that the cable supports up to as high of PDP = 240W as defined in the USB PD specification.

USB PD EPR Flow 240W
Example of a Normal EPR Mode Operational Flow

240W can be delivered using 48V up to 5A. You’ll find the full details both in the latest USB Type-C 2.1 and USB PD 3.1 specifications that can be found on here and there.

Via Liliputing

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1 year ago

What is the use case for this? When is it a better solution to use a special USB-C power supply with a special USB-C cable rather than just a regular power brick?

1 year ago

Cross compatibility between OEMs.

I have a container box full of chargers collected over the decades, that is still working but no device to use it on.

1 year ago

As real world example:

  • I have Thinkpad with type-C 60W power adapter
  • docking station have 140W power brick with it’s own plug and strange “dock” socket in notebook itself which looks like 2 type-c side by side. One of them is real USB/Thunderbolt and another have very strong wires, I think just for power.

In example above manufacturer have to have 2 different power adapter cables. With this new one it can make them same as in the past.

1 year ago

Without enforcement of TM and standards, this another mess of subpar product waiting to be release.

1 year ago

@Jean, this is unrelated and I’m commenting here because comments are disabled on sponsored posts on your website.

Should you be allowing posts like

They’re notorious for selling keys to users that Microsoft disables later on because they’re actually pirated. These websites are operated from a certain country where accountability does not exist (in many cases hosted elsewhere, but you know who runs them and from where).

1 year ago

all power over ethernet 48vdc show a 70-85% effiency to 1.8-3.3-5vdc, in addition of power loss from common ac supply 19v. it’s not a big deal for small 10w usb power device.
AC to 19v -> buck to charge li-ion battery -> step up to 50v -> buck to 5vdc sorry 40% energy loss