USB-C PD power output limit on FW13 7040?

Framework Laptop 13
1

I’ve noticed that when charging my phone (Note 20 Ultra 5G) from the USB-C port on FW13, the charging will be frequently interrupted (~1min. intervals). I noticed that this eventually stops after the battery level on the phone reaches somewhere between 60-70%.

Since this phone supports up to 25W charging speeds, my suspicion is it is trying to draw too much power. When the charging rate slows down as the battery fills up, the issue goes away.

What is the maximum PD output power supported by the FW13’s USB ports, and what capability is reported to the connected device? (max voltage, max current, PPS mode?)

2

5v, don’t recall the current, but I do believe it will be less than 5 amps, so you won’t get 25W, no PPS. It’s not meant to be a high wattage power supply.

It’s older info but:

I don’t recall any mention of newer mainboards being any different.

Current drops at the upper end with li-ion charging, so things ease up at that point.

3

I used a USB-C power meter to measure it.

Upon first connecting the phone, it pulls 5v 2A. This causes the bus power to quickly reset, after which the phone pulls 5v 1.75A and no longer reports “fast charging”. At this point it will still keep tripping the USB port, but more slowly.

This is all with the laptop turned off/hibernated.

So it seems like that 1.5A limit is in effect here, not the 3A.

4

See the paragraph where is explains power to the ports.
They are all at 5V, so if you want to get to Watts. Watts = Amps * Volts. So just multiple the A figures their by 5.

As a point to note, the FW USB ports are not really suited for charging external devices as their power output is so low.

5

Interesting, I wonder why my phone isn’t negotiating more power. Good to know the intended spec.

I’d guess that the subsequent dropouts in my case take too long for the phone to recognize something wrong and back off further from 1.75A to 1.5A.

6

It might not be made to do higher wattages at 5v. It may only do more if there are higher voltages.

Fast charging & USB in general is such a mess when it comes to labeling and advertising abilities. The USB IF spec organization could have mandated that if you wish to a use any of their trademarks or names that you must label ports & clearly state abilities boldly in all marketing. But naming and such has never been something they know how to do. Perhaps we should be glad USB-C isn’t called USB 3.5 micro, revision 2 ultra-super speed