USB-PD 15V mode issue

OK, trying it with a more normal adapter (Samsung W16-030N1A, 30W). Still only pulls ~230mA, and the trace is a bit more normal:

6911793-6913972 USB PD: Full text: #1    (2879.913750ms): (r2) SRC[0]: SOURCE CAP - [1] [Fixed] 5V 3A (15W) [unconstrained] - [2] [Fixed] 9V 3A (27W) - [3] [Fixed] 15V 2A (30W)
7717970-7720149 USB PD: Full text: #2    (3215.820833ms): (r2) SRC[0]: SOURCE CAP - [1] [Fixed] 5V 3A (15W) [unconstrained] - [2] [Fixed] 9V 3A (27W) - [3] [Fixed] 15V 2A (30W)
7720512-7721700 USB PD: Full text: #3    (3216.880000ms): (r2) SNK[0]: GOOD CRC
7728937-7730445 USB PD: Full text: #4    (3220.390417ms): (r2) SNK[0]: REQUEST - [1] (PDO #3: Fixed 15V) 2A (operating) / 2A (max) [comm_cap]
7730759-7731966 USB PD: Full text: #5    (3221.149583ms): (r2) SRC[0]: GOOD CRC
7733627-7734834 USB PD: Full text: #6    (3222.344583ms): (r2) SRC[1]: ACCEPT
7735201-7736390 USB PD: Full text: #7    (3223.000417ms): (r2) SNK[1]: GOOD CRC
8192161-8193368 USB PD: Full text: #8    (3413.400417ms): (r2) SRC[2]: PS RDY
8193734-8194923 USB PD: Full text: #9    (3414.055833ms): (r2) SNK[2]: GOOD CRC
8215655-8216844 USB PD: Full text: #10   (3423.189583ms): (r2) SNK[1]: DR SWAP
8217162-8218369 USB PD: Full text: #11   (3423.817500ms): (r2) SRC[1]: GOOD CRC
8219302-8220509 USB PD: Full text: #12   (3424.709167ms): (r2) SRC[3]: REJECT
8220874-8222063 USB PD: Full text: #13   (3425.364167ms): (r2) SNK[3]: GOOD CRC
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FYI we traced this issue to an alternate source FET in the charging circuit. When the input voltage and battery voltage are very close to each other, the charger will operate in buck boost mode, and when this happens with the alternate source FET, the charger cannot fully switch the high current FET on and off, which causes the low input current that is observed.

If you are running into this issue, use a 20V charger, or a 12V charger. We recommend a 20V 60W+ charger to get the best performance from your system.

Supporting as wide an input range as possible is mostly to allow charging the laptop in situations where you may not have the correct charger but need to get some extra life out of the system.

So far not many people seem to be impacted by this. But if there is a large impact we could disable negociating 15V.

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Thanks for investigating.

I’ve come across a lot of 15V chargers in daily usage, as 30W and 45W adapters aren’t that uncommon. 12V isn’t a required PD voltage anymore, so <=45W chargers aren’t guaranteed to have it, and 30W-45W should be plenty of power to keep the system running and slowly charging under most usages so there’s no requirement for 20V to be available, either. With USB-C, there’s no such thing as a “correct” charger; all devices should just work at supply wattages that are reasonable (as supplies are required to provide standard voltages at those wattages). Maybe most of your users are still stuck in the pre-USB-C way of only using the charger that comes with the device, but keep in mind that people can choose not to include your charger when purchasing a Framework laptop, so I’d say Framework is more progressive in its view on USB-C charging.

Anyway, please contact me about potentially exchanging my MLB for one that has been screened to have the primary-sourced FETs.

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Thanks for the update, Kieran. I really appreciate it.

It would be fantastic if you guys could offer the option of disabling the 15V mode for machines that are affected by this issue. I just checked my 15V power bank, and while it doesn’t have a 12V mode, it does support 9V at its full output power. That would definitely be better than nothing.

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There is a method of updating that does not require you to install Windows

Not really related to the whole point of the thread, just want you and anyone else who stumbles across this thread to know

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There’s no reason to use Windows to Go to install the BIOS update; all BIOS updates from 3.07 forward have UEFI flashers (with fwupd coming): BIOS 3.07 + Windows 10 and (11 Alpha) driver bundle

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I have this issue as well and originally thought it was a bad battery on my new batch 6 laptop. Using the Nintendo Switch charger (HAC-002 5v @ 1.5A or 15v @ 2.6 A) over night does not charge the battery. It does charge it a tiny bit (~30min on time) if the battery is completely dead. Using a Samsung EP-TA10JWE USB A 5.3v @ 2 A charger will charge the laptop about 50-75% over night.
It is a bummers as I was hoping to reuse the Switch charger and avoid adding another charger to my bag. Getting a 60W appears to be the solution and avoids the scenario of a 30W not keep the laptop on for extended heavy use.

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The big shame of the 15V issue is that USB-C PD external batteries are very very rarely 60W, but a 30W one will easily help to extend a laptop’s battery life (or charge it if not being used much). Losing that on the Framework is really quite a shame…I hope they are able to correct the problem rather than just switch it off.

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If you’re running into that issue, and only want to carry one charger, you can always do what I do: carry a 60W 5/9/15/20V charger. and use that to charge your Framework, Switch and/or other devices. A properly made device should always negotiate down to what it can handle… Right?

It’s not exactly a workaround, nor is it cheap if you don’t own a 60W charger, but it does address the one-charger issue.

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Doesn’t address the issue of USB-C batteries though :slightly_frowning_face: I have a small mountain of high power USB-C wall power supplies, but in the car and away from the mains, 30-45W is as good as it usually gets…

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Yeah, if this is a hardware limitation you should look into disabling the 15V profiles and only claim to support 9V or 20V (if available).

Half of the chargers in my house are 45W (with 15V/3A as the highest voltages supported). It’s super fustrating to plug it in and see it discharging.

Losing the 15 Watt charging option would be an issue for me because I use that in my car. I hope it gets fixed soon

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We are thinking to offer an option to disable 15V source negotiation in the bios to allow charging from these chargers and negotiate a lower voltage in a bios update.

If you are interested in the parts that are impacted, they are PQB10 and PQB11 on the bottom side under the fan.
image

The good FET is AON6354 1N DFN5X6-8 -D
Please note these fets have a large exposed pad under the package, and there is some via stitching to other layers.

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Thank you Kieran. Those pics and part numbers are awesome.

Did I find the right part on digikey? I guess it’s super out of stock (42 week lead time).

Yeah, I guess a rework would be doable for me and dnschneid (assuming we can get the part), but not a lot of other people.

The BIOS option to disable 15V would be appreciated (though it would be cooler if you could autodetect it based on SKU or something if that’s encoded anywhere).

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You could try checking Octopart
https://octopart.com/search?q=AON6354&currency=USD&specs=0

If you wanted to search for alternate parts, the AON6354 has a gate capacitance of 1330pF, but the other source with the issue was around 2806pF. So if you found a similar part you could probably sub it in. Obviously I can’t guarantee results.

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ahem

more battery stuff

The reason you don’t have a 65W power bank is because most power banks use cheap cells that don’t have sufficient output.
The one on my unit uses 3200mAh*6 Simplo Technology LC32SD129Q-6 official rating for 71WH (66WH after considering energy loss during voltage boosting). Divide that it means each cell must be able to consistently output 3.7V at 2A. Most off the shelf 1000mA ones feature 3 cells with 12W divided among them, for 4W each cell and at most 1.3A per cell, and even then those units get warm.
My friend spent nearly $200 and got himself a 100W absolute clunker, packing 26800mAh or 100WH of oomph. Although I’m sure he didn’t find much use of it just like I did.

You might be wondering why is those power bank super expensive. In one part lies in the fact that they have an actual battery monitor/balancer that gently balances out the voltage of each cell when charging and make sure none of the cells overdischarge. Then you need the circuit to be able to handle 65W voltage conversion/leveling. Then you need the batteries to be able to handle the 65W of output without exploding. Then you need all of that to be able to take 65W and top itself up in exactly an hour.

There are some 45W ones, if I remember correctly. Like this one

Even though the absolute maximum rating seem to be still 60W. weird.
Anyhow. USB-PD actually have a weird quirk where despite the regulation saying that you MUST supply 20V with at least 2.25A (for 45W), some chargers like the Anker 711 is able to negotiate a 20V 1.5A which, while it makes laptops complain, they will still end up taking it, often times actually charging it up as you use it. Albeit, very very slowly.

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Not quite. Here’s the requirements table from the PD spec:

At exactly 45 W, 20 V is not required at all. Anything above 45 W does require 20 V.

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My saying is that in order to supply 20V to the rail the charger must be at least capable of 45W, according to specifications (instead of the 20V at 1.5A like I mentioned) and also as you mentioned, 20V 1.5A worked just fine. However there are not a lot of 30W power banks (if any) that can do the 20V 1.5A.

They do claim that the laptop can charge from basically anything, like a 9V 2A or whatever conglomeration of a “QuickCharge 3.0” nightmare it is.

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This is not true. The spec does not forbid low-wattage devices from offering additional voltage rails as long as the advertised current does not exceed the source’s max power (see section 10.2.3).

This I definitely agree with. I wish there were some, but so far I have not found any. I’ve been considering building my own, though having the option to force the Framework laptop into 9 V mode would be much easier and meet most of my needs.

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There are more 65W than 30W. And some more 45W.
This 30W I found https://www.amazon.com/dp/B07R716V2V/ bumps right up to the capacity limit of 100WH and indeed deliver only a maximum of 30W. But it doesn’t do 20V out.
I still think a 20V output will be handy since basically any other computer is unable to take a 9V/12V/15V input. Although since you have Framework you can have it act like the “power adapter” and charge the other devices

Which goes to show the mightiness when tech work together and engineering/ingenuity that goes into them, and the necessity/benefit of not cutting corners. I had once “jump-started” my father’s Macbook with my Dell because he forgot to bring a charger and I can just continue to use my Dell plugged in because the Dell have both a barrel jack and a Thunderbolt
Whereas my Lenovo T14S decide to fry my Dell instead

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