USB-C specification revision 2.1 brings up to 240W power delivery

jsilva

Posts: 325   +2
In brief: The USB Implementers Forum announced a new revision to the USB-C standard. With the USB-C revision 2.1, the interface's power delivery will be upgraded from 100W to 240W, allowing devices such as 4K monitors and TVs, printers, and even gaming laptops to be powered via a USB-C interface.

The USB-IF announcement indicates that the 240W power option is called Extended Power Range (EPR). To handle 240W of power, the USB-IF changed the USB-PD spec. While the amperage will still be configurable up to 5A, the maximum voltage has been increased from 20V (USB-C 2.0 standard) to 48V.

The EPR cables will need to meet some requirements to handle the extra power, including support for 5A and 50V, a minimum functional voltage of 53.65V, and electrical components such as bypass capacitors rated for a minimum of 63V. USB-IF also recommends the use of snubber capacitors on each end of the cable to prevent arcing damage when unplugging.

Moreover, the new cables should be electronically marked and properly identified so users can easily distinguish them from standard USB-C cables. However, there won't be any physical changes to the plugs, so users can plug a USB-C 2.1 device into a USB-C 2.0 port and vice-versa without issues.

With the new standard, USB-IF also announced the deprecation of Standard Power Range (SPR) cables. The institution stated that devices supporting the higher wattage of the USB-C 2.1 standard should be available on 2H 2021.

If USB-IF keeps increasing the maximum power delivery supported on a USB-C interface, it may be just a matter of time before it becomes the new standard to charge laptops. USB-C is already widely used as a charging port, but the most power-hungry gaming laptops usually need more than 240W to power the whole system.

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Is this really correct? 240 watts of power, and the usb puts out 5v, comes up to around 48 AMPS of current?
 
You should look up wire sizes for 200W delivery.
Wire sizes don't depend on power delivery (Watts), they depend on amperage. The specification didn't change any the amperage, it increased voltage to increase power delivery to 200W (Amps x Volts = Watts).
Is this really correct? 240 watts of power, and the usb puts out 5v, comes up to around 48 AMPS of current?
Nah, it's the other way around. 240 watts of power provided by 5A and 48V.
 
Interesting spec improvements. If the cable is super thick though, it will be of limited usefulness. Our current fleet of laptops is USB C powered, and after 3 years the weight of the thicker dock USB cables is causing the USB C ports to loosen and fail. I cant imagine a thicker, stiffer cable will fare any better.
 
I wonder when thunderbolt will be updated to support the new charging wattage? As far as I can tell, thunderbolt maxes out at 100W. But thunderbolt also carries usb data, displayport, pcie, and it even has the ability to do peer to peer networking via tcp/ip.

I wonder if usb-c will eventually replace the connectors on our video cards, power supplies, etc. The connectors are much smaller, and cable management would be so much easier if we use usb-c.

For instance, imagine a corsair rgb fan setup with a single usb-c cable for power, data, and rgb. Or how much sleeker our video card setups would look if we could use usb-c for power delivery instead of two or 3 8-pin connectors. Or even hard drives, e-sata needs two cables for power and data. All of that could go away if we use usb-c for power delivery and usb/pcie data.
 
I wonder when thunderbolt will be updated to support the new charging wattage? As far as I can tell, thunderbolt maxes out at 100W. But thunderbolt also carries usb data, displayport, pcie, and it even has the ability to do peer to peer networking via tcp/ip.

I wonder if usb-c will eventually replace the connectors on our video cards, power supplies, etc. The connectors are much smaller, and cable management would be so much easier if we use usb-c.

For instance, imagine a corsair rgb fan setup with a single usb-c cable for power, data, and rgb. Or how much sleeker our video card setups would look if we could use usb-c for power delivery instead of two or 3 8-pin connectors. Or even hard drives, e-sata needs two cables for power and data. All of that could go away if we use usb-c for power delivery and usb/pcie data.

It's been feasible for 90% of laptops since Thunderbolt 3 (like 5 years ago). The only product line where 100W is not enough is high-end gaming laptops. So the biggest obstacle is not the USB standard, it's the OEMs themselves. They just love selling their proprietary overpriced junk chargers and docking stations.

The worst is when the laptop actually does have TB but they use some kind of trickery to restrict that to their own junk. Such as the Dell XPS line - it just complains the charger is "not supported" or something, and refuses to charge. And it's not a low-end Chinese cr@p charger, it's a $1300 LG TB monitor, which works just fine with some other brands.

The other mindf*ck is when the TB port on one side only supports display, and the one on the other side only supports charging. All Windows laptops that I've seen with TB ports do this.

This is one of the many reasons why I'm more and more inclined to switch to a Macbook, only Apple seems to get this right (which is beyond ironic). I hate the mess these Windows OEMs are creating.
 
I wonder when thunderbolt will be updated to support the new charging wattage? As far as I can tell, thunderbolt maxes out at 100W. But thunderbolt also carries usb data, displayport, pcie, and it even has the ability to do peer to peer networking via tcp/ip.

I wonder if usb-c will eventually replace the connectors on our video cards, power supplies, etc. The connectors are much smaller, and cable management would be so much easier if we use usb-c.

For instance, imagine a corsair rgb fan setup with a single usb-c cable for power, data, and rgb. Or how much sleeker our video card setups would look if we could use usb-c for power delivery instead of two or 3 8-pin connectors. Or even hard drives, e-sata needs two cables for power and data. All of that could go away if we use usb-c for power delivery and usb/pcie data.
I think at somepoint, using USB-c for everything would get confusing and be more of a problem. Think of walking up to a power strip with 8+ plugs in it and trying to figure out which device it's connected to. And just unplugging something isn't too much of a deal, but what if you take your PC out to work on it and then you have to connect everything BACK to it. What connector goes to the video card? How does stuff like port forwarding work?

maybe I'm exaggerating but I think keep dedicated connectors is mostly a good idea. We've gotten to the point where I think HDMI+ Eithernet cables and usb for everything else is the perfect combination. It's not like way-back-when when you had 2 different types of serial ports, a VGA port, PS/2 connectors for mouse and keyboard with USB ports if you were lucky.
 
I think at somepoint, using USB-c for everything would get confusing and be more of a problem. Think of walking up to a power strip with 8+ plugs in it and trying to figure out which device it's connected to. And just unplugging something isn't too much of a deal, but what if you take your PC out to work on it and then you have to connect everything BACK to it. What connector goes to the video card? How does stuff like port forwarding work?

maybe I'm exaggerating but I think keep dedicated connectors is mostly a good idea. We've gotten to the point where I think HDMI+ Eithernet cables and usb for everything else is the perfect combination. It's not like way-back-when when you had 2 different types of serial ports, a VGA port, PS/2 connectors for mouse and keyboard with USB ports if you were lucky.
Fair point, the potential for confusion does exist. But manufacturers could label their connectors, or color code them. Also, the power supply and the components can negotiate the requisite voltage/current on their own via the usb-pd protocol. So as long as the port on the power supply can supply the necessary device power, inadvertently interchanging cables shouldn’t matter. I’ve used different cables and charging bricks on my MacBook, and according to my usb-c tester, the MacBook draws the same amount of power regardless of which cable or power adapter I use. Give or take a few milliwatts.

I know there’s a reason why we use dedicated cable connectors for the various components, but is the reason anything more than just a legacy reason? User confusion is one obstacle to overcome. Perhaps power supply cost/complexity is another, given the various chips inside the power supply that would be needed…?

I don’t know, but just an idea of mine. The smaller form factor connectors could save space on mini itx boards, etc.
 
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Fair point, the potential for confusion does exist. But manufacturers could label their connectors, or color code them. Also, the power supply and the components can negotiate the requisite voltage/current on their own via the usb-pd protocol. So as long as the port on the power supply can supply the necessary device power, inadvertently interchanging cables shouldn’t matter. I’ve used different cables and charging bricks on my MacBook, and according to my usb-c tester, the MacBook draws the same amount of power regardless of which cable or power adapter I use. Give or take a few milliwatts.

I know there’s a reason why we use dedicated cable connectors for the various components, but is the reason anything more than just a legacy reason? User confusion is one obstacle to overcome. Perhaps power supply cost/complexity is another, given the various chips inside the power supply that would be needed…?

I don’t know, but just an idea of mine. The smaller form factor connectors could save space on mini itx boards, etc.
Well going specifically to the desktop side of things, what if you plug your mouse into the videocard instead of plugging in the monitor.

I also don't think this is a legacy issue. With things that are universal, you end up with something that does everything well or okay but nothing great. Specifically for networking, I think this could be horrible for things like managed switches. I know on my home network I use a managed switch. I can imagine that if I use a USB cable as a network cable that if I unplug it from port 1 and accidentally plug it into port 2 it could cause chaos in my switch.

I'm also not a fan of higher voltages being output by a single port. Having a seperate power comnector adds an extra layer of surge protection from the PC. If the monitor blows up, I don't want it sending all that voltage or current back to the PC and potentially killing thousands of dollars in components. It certainly has its place but I just feel like it's advantages will come with more disadvantages than our "legacy" connectors
 
Well going specifically to the desktop side of things, what if you plug your mouse into the videocard instead of plugging in the monitor.

I also don't think this is a legacy issue. With things that are universal, you end up with something that does everything well or okay but nothing great. Specifically for networking, I think this could be horrible for things like managed switches. I know on my home network I use a managed switch. I can imagine that if I use a USB cable as a network cable that if I unplug it from port 1 and accidentally plug it into port 2 it could cause chaos in my switch.

I'm also not a fan of higher voltages being output by a single port. Having a seperate power comnector adds an extra layer of surge protection from the PC. If the monitor blows up, I don't want it sending all that voltage or current back to the PC and potentially killing thousands of dollars in components. It certainly has its place but I just feel like it's advantages will come with more disadvantages than our "legacy" connectors
Let me clarify that I didn’t mean developing a single port to power all the pc components; instead I meant replacing the existing internal connectors such as molex, eps, pwm, and pcie 6/8 pin connectors with usb-c ones. Same thing on the power supply side. And let the power supply and the various devices negotiate the amount of voltage/amps to use. So instead of two pcie 8-pin connectors on a GPU, how about just one cable that can supply the necessary wattage?

Why would somebody plug their mouse or other peripheral into the internal usb-c power port of their video card and expect the video card to power on? At some point you have to expect that people will do the right thing and follow the manual or have some “common sense.”
 
Wire sizes don't depend on power delivery (Watts), they depend on amperage. The specification didn't change any the amperage, it increased voltage to increase power delivery to 200W (Amps x Volts = Watts).

Nah, it's the other way around. 240 watts of power provided by 5A and 48V.
No, 240W @ 5V =48A. (240/5=48)
 
It’s 48V at 5 amps. Read the new spec. The current spec of 100W is 20v at 5amps. Use a usb-c tester and you’ll see the voltage rise all the way to 20V.
USB is 5V. Sure, curent USB-C can scale to 20V @5A but on paper, not on many PC motherboards, because we don't have 20V power source. For phone chargers in the wall it's a bit different since your starting point is way higher than 20V...
 
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USB is 5V. Sure, curent USB-C can scale to 20V @5A but on paper, not on many PC motherboards, because we don't have 20V power source. For phone chargers in the wall it's a bit different since your starting point is way higher than 20V...
Usb-a is up to 5v yes, but usb-c is up to 20v at present, and will go up to 48v under usb-pd 2.1. Usb-a was developed many moons ago, and while the original spec was low voltage and current, usb has evolved, and now Usb-c has power delivery.

Your point about usb-a not scaling to 20V on motherboards is true, other connectors are used to power motherboard components like video cards or sata drives or the eps cpu connector. But Some newer z590 motherboards have thunderbolt4 and the usb-c connector delivers up to 20V@3A (60W) (see the z590 vision d).

I posed a question on why those older connectors couldn’t be replaced with usb-c connectors, but at least one person thinks it’s not a good idea because users may be confused by which usb-c belongs to which peripheral. I tend to disagree, I think If usb-c can deliver up to 240W, it’s worthwhile to consider moving on from the old relatively large power connectors like molex, 6 or 8 pin pcie connectors, and so on, and shrinking them down to usb-c.
 
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