USB power information

There was a article about this a while back on a big dutch techsite.

I quote: "The promising tangle of USB c - One cable that can virtually do everything".

It is about the different types of USB connectors and protocols/standards.

Here are a couple pieces from that article;

Usb type c versus usb 3.1 gen 1 en gen 2

Usb-version speed encoding Connectors
Usb 2.0 (incl usb 1.0 en 1.1) up to 480Mbit/s 8/10bit Type a, b, mini, micro, c
Usb 3.1 gen 1 up to 5Gbit/s 8/10bit Type a, b, mini, micro, c
Usb 3.1 gen 2 uo to 10Gbit/s 128/130bit Type a, b, mini, micro, c

Usb 3.1 gen 1 was formally known as usb 3.0.

As you can see only the speed and coding differs from 3.1 gen 1 and 3.1 gen 2. All the 3 protocols can use the different connectors.

Power delivery

There is an optional power delivery protocol, PD for short, that was introduces together with usb 3.1 and the new usb c-connector.

This PD protocol consists of 5 different levels that describes the different currents and different voltages.

PD Profiel 5V C 5V P 9V C 9V P 12V C 12V P 15V C 15V P 20V C 20V P
1 0,1A - 3A 0,5W - 5W na na na na
2 3A 15W 1,7A - 3A 15,3W - 27W 1,5A 18W
3 3A 27W 3A 36W 1,8A - 3A 27W - 45W
4 3A 45W 2,25A - 3A 45W - 60W
5 5A 60W 3A - 5A 60W - 100W

The type A and B connectors have a max voltage of 5v and the current is typically limited to 2A.

Only the new type c connector can be used with different voltages.

PD can be used with all the usb protocols (usb 2.0, usb 3.1 gen 1 and usb 3.1 gen 2), as long as the cable uses the type c connector.

To prevent damage to client and host or when using non PD capable equipment the voltage will remain 5V and current will be limited to 1.5A.

This isn't meant to criticize you or your article, just as some extra info for everyone that is interested.

You have done an awesome job writing this! Very informative. :THUMBS-UP: :beer:

The general problem with USB-C is complexity and density. You need special chips to handle it and you need a very fine pitch on the circuit board to handle the connector.
The chips has to be developed first and must be fairly low cost for many applications, it may also be an extra chip in many cases for the next few years (For current only the chip can be avoided).
This means usb-c will first show up in high volume, high tech equipment with a fast development cycle, like phones.

When writing the above article I was very much in doubt about how much general usb/usb-c information to include, I hope the balance is acceptable.

That is not correct, PD are only allowed on USB-C connectors. The standard was changed.
Current is depend on the coding resistor and can be up to 3A.

But it looks like the information is incorrect.

Hmm,- it is directly copied from my source.-
I think it’s just a translation error…. I just re-read the article, and you are right. :person_facepalming:
However, the PD protocol can indeed be used with all the USB protocols (usb 2.0 and usb 3.1 gen 1 and 2. But only when they use the type c connector)

Unfortunately the article doesn’t say anything about resistor coding… Only that the power is being ‘negotiated’ between the 2 devices.
I know that the new type c cables will have a special microchip in them to be able to communicate with the device.

I’ve edited the text. Hope its correct now. :slight_smile:

Not always, you have the following type C cables:
USB 2.0 without chip
USB 3.1 gen 1 without chip
USB 3.1 gen 2 without chip (I am not sure about this one)

USB 2.0 with chip
USB 3.1 gen 1 with chip
USB 3.1 gen 2 with chip
USB 3.1 gen 2 tunderbold with chip

And there is no marking on the cable saying what it is and you cannot see it on the cable (The old usb standard was a bit easier in that regards).

+1

Thanks for the very informative simple to read article HKJ. :+1:

Kudos to thee HKJ!

Regarding all of this power delivery standardizations, all I have to say is…

What a mess! :FACEPALM:

Cheers ^:)

Barkuti, you’ve been raiding my stash :wink: I’ve got twice that easily since I’m in the habit of grabbing all decent-looking wall-warts and USB cables I come across for free. Most are given away but my stash seems to grow faster anyway.

Good info on this subject as we’ve come to expect from HKJ. While it was touched on, something I’d like to add is that like LiIon cells you want to use only good cables. With better products the supplied cables are usually good, but with budget products the supplied cables are sometimes a target for cost-cutting and they may not last long at all.

Among us dashcam hobbyists it has became well known that cheap USB charging cables are one of the most common trouble spots, leading to many different malfunctions. These devices usually need at least a full amp at the camera to work reliably with some needing more. Cheap cables oxidize quickly, conductors break with movement, and connections get dirty which can lower the current flowing into the cam and cause problems. A cheap cable can work fine when new but fail to deliver the needed current a month later even though it looks good and wasn’t abused. The good cables will long outlast the cheap ones so they are a better deal even with their higher initial cost.

Also mentioned was the possible degradation of batteries due to overheating. While the evidence is only empirical, dashcam users universally have problems with LiPo batteries in the hot environments that many are used in. These batteries can go bad in as little as a few weeks in the hottest climates. Good quality batteries last longer but it’s hard to know the good from the bad as those who sell generic replacements rarely list the battery’s build source and it’s not branded on the shrinkwrap like LiIon cells are. So I’d change HKJ’s “conjecture” to a near-certainty regarding battery damage through overheating.

Phil

Thanks. Very useful. I’ve been picking up bits and pieces as I’ve been going. You’ve filled in a lot of the many gaps I had left.

I need to get a little further along on my understanding of QC2. I’ve been waiting on some QC power sources so I can start experimenting.

I will say, I think ADB deserves a mention in the history of peripheral buses, especially since it was a universal (for Apple) serial bus, and Apple ditched it and went all-in on USB before most PC makers really committed.

WOW - great source of info!

thanks HKJ

You are probably right, it is just that I always have used a PC and not really looked at Apple computers.

Thanks for sharing!

Very nice compilation of info. I like the history refresher having lived through it from the beginning.

What do you use to negotiate quickcharge voltage levels for testing?

My own box, a Arduino nano with a few resistors. I needed something that do not use power from the usb power and allows me to connect my load in a four terminal hookup.

Thanks. That’s what I’m planning on doing since I haven’t found anything that someone else has already designed/tested for incorporation into otherwise dumb electronic devices.

Great job. Thanks for sharing.

That was educational. Thank you for the time to share that.

I’m using Samsung smartphone and the charger came with it is the Adaptive Fast Charging type,

while using Blitzwolf QC2.0 wall adapter or QC2.0 powerbank, it seems unable to do fast charging, what am I missing and what should I do to enable fast charging?