That is exactly what my module is designed for.
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Theoretically you could give it up to 40 volts and it should be able to regulate it to whichever PD profile is closest and whatever the device requests, this will not step up only step down.
I can do PD profiles 5V/3A 9V/3A 12V/3A 15V3A 20V3A.
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Said module already exist.
The problem is that almost all of these modules do step-down only, so you can only do, say, 15V when the input is higher than 15V and 20V when the inout is higher than 20V.
However because how USB PD can (at least, in theory) support anywhere between 5-20V, having a lower voltage usually donât cause any problems.
Dell have made a similar module, except it also do 20V and it look a bit nicer.
Unfortunately this product no longer exists. It was incredibly cool when it exists.
Fortunately I had DIYed one by (basically sticking that Jacobspart board) onto a Dell barrel jack (from a spare charging port of a Dell laptop). The Dell brick only do 19V but the laptop doesnât seem to complain.
Make it into a expansion card? no. Itâs much more useful as a standalone item (because you can charge other things with it). Also the circuitry is quite large (caps, the inductor, etc) and probably wonât fit.
Alternatively you can get one of these and just cut the car plug off and modify it.
https://www.amazon.com/CASIMY-Vehicle-Adapter-Chromebook-Cigarette/dp/B09NLWZCZ2/
This one probably include a step-up and a step-down, hence the large volume.
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the battery is charged serially (which means it will need to be stepped up) and regulated parallelly. However, this is done by a battery-charging circuitry (something a operating system have no control over)
Mostly correct. Framework is one of the very few laptops that can charge over 5V, if I didnât remember incorrectly.
Except itâs not really the cables but the (rather fragile) contacts in the USB-C connector.
Because ⌠itâs not intended this way.
If you absolutely dig in, you can probably find the power rail where the input voltage is fed into the battery charging circuit (or the power regulating circuit), and feed it 12V (or some similar voltage). The system will probably freak out (because it did not detect a port from which it is being charged with but the battery circuit is working)
USB PD as mentioned have the handshake (which must be done in order for a device to legitimately sink non-5V current), so even if you feed 12V to the port the computer wonât know what to do. Is the USB trying to sink current? Is it a USB device error? What kind of device is attached to it? Is the orientation of the connector wrong? so on and so forth.
If anything, it should trip the internal (resettable) fuse and you get a âUSB device not workingâ error. If that 12V doesnât just get dumped to the 5V rail and fry everything.
On a device with a regular DC jack (and even those have a signal pin to detect the ratings of chargers) you can just supply (whatever the rating is, usually around 19V) DC to the port (as long as you can source the current) and the computer will happily charge away. Maybe it will throw a âunknown AC adapter attachedâ error (because the charger sense didnt detect anything) but thatâs about it.
It make sense from a device manufacturer or connection protocol perspective to put on checks (e.g. power supply rating check, USB device type and power requirements) so the computer will not cause harm to anything (e.g. overloading the charger, frying peripherals) even though the peripheral might have its own protection (e.g. overcurrent/overtemp protection, fuses) while being able to work with them (regulate the speed of charging, providing 20V to other attached laptops when their battery level is low, provide 5V to attached phones and 9Vs to quick-charge enabled tablets) that, well, require some âsmart-nessâ for proper function.
If you want, you can crack (or mod) the car charger to take 12V DC (through a barrel jack or something convenient). This way you can have the charger convert (likely a buck or a DC boost + switcher) do 5V for your other devices.
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I might be in the minority here, but I would prefer an ungrounded design with folding prongs.
I donât see a huge benefit to grounding the unit since itâs made of plastic.
I do see a huge drawback, which is that in many countries (Japan, Taiwan, etc.) earthed outlets are not commonly available.
I realize you can use different cables and adapters to defeat the ground, but I think apple has a much smarter design here (ground only if you want it).
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Grounding is important for the laptop itself and not for the power supply. Otherwise you as a user ground the laptop (through the touchpad in the worst case), which can create erratic inputs. There are several reports of such problems with crappy ungrounded power supplies on the Framework laptop and also on other brands.
If the Framework laptop comes to these markets, Framework can surely figure something out by shipping a special version of these power supplies.
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But the AC and DC side should be isolated, so itâs not a big safety issue unless Iâm missing something regarding the laptopâs operating voltage?
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No, GROUND is always connected in anything with mains power, It isnât technically isolated through the PSU if you look at grounding. When charging the main body needs to be referenced to ground meaning that they should be at the same power level.
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Macbooks have shipped with no Earth pin for most of their laptop chargers since forever and none suffer from any input issues. Grounding isnât the issue â itâs how well the charger is built. Iâve run my Thinkpad and now my Framework off of RavPower ungrounded USB-C adapters for almost a decade now, without any issues.
Exactly. Depending on the design, an ungrounded power supply will only be connected to the the mains wires. Theyâll obviously not be connected to the low voltage side, but filter capacitors between mains and the low voltage side are common (and often required) . There might also be small leakage currents through the power supply. All of these things can under some circumstances push some unintended voltage level to the laptop case. Especially if the laptop isnât grounded using other means (like with an HDMI or LAN cable).
So grounding is usually a little bit simpler and safer than designing a special power supply that will work flawlessly without ground connection. Not that thatâs impossible.
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If itâs been designed right, which it should be since itâs made by a PSU company.
Then all it needs is a different cable.
You are missing the point. Yes, cables like this exist:
But guess what, no one connects the ground because there usually isnât anywhere to connect it to.
This is why almost all USB PD travel chargers do not require a ground - because in some countries it simply isnât available.
The Framework charger is maybe an okay design for leaving at home, but as a travel charger, having a detachable cable already makes it pretty unworkable IMO. The fact it requires a ground makes it even worse.
Strange that the charger for a laptop built in Taiwan is basically unusable in Taiwan.
You will not find type B (NEMA 5-15) outlets in residential applications in Japan and Taiwan.
Only NEMA 1-15 (type A)
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Type A = ungrounded
Type B = grounded
The Framework adapter isâŚgrounded
Outlets in North America accept both type A and type B.
Outlets in Japan and Taiwan look like this and only accept type A.
I donât understand what it is you arenât understanding.
The adapter framework sells requires a ground. Outlets in Japan and Taiwan do not have a ground.
I have several C13 to 2 pin Australian plugs. That donât have that ground cord.
Yes, and this is exactly why we need to ground it (e.g. earthing)
Because without earthing, there is no reference to the DC side what â0 voltageâ means, and thus in reality a ungrounded power supply will actually output AC 9.75V (and -9.75V) instead of 19.5V. if you reference to ground.
You can see my full post here.
Which is why I think the Type-B plug is very clever
Because in addition to fit its own 3-prong it also fits the 2-prong.
We wonât be having this conversation if all the outlets ever manufactured only have 3-prong -variants of the sockets. But people are stupid/lazy and they want to save cost, so they designed âtwo-prong onlyâ stuff, ranging from sockets to extension cords.
This, however, will be more annoying for countries like China, that use Type-I for the 3-prong and type-A for the 2-prong (the 2-prong wonât fit into the 3-prong), so people have to invent this ⌠thing so their power strip can stay compact.
The round EU plugs (Type E and F, sometimes C) is not naturally a problem, IF, as I said, every socket (not necessarily the plug) in the world is a 3-prong. But no, not this time.
Great Britain, however, probably set the best example here â absolutely everything is grounded, and every single plug is 3-prong. With a fuse, too. Apple even have to make a special wall-wart for this country.
(on the side note, why on earth is there 20 different plus styles? Canât we just agree on something?)
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I see threads like these and it at least makes me think there is still one benefit of living in the UK over most other places. 
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UK plugs arenât necessarily grounded. The most common solution for phone and laptop chargers is to have a dummy (plastic) ground pin for the sole purpose of opening the shutters.
I should also point out that the IEC C5 to type C europlug contraption pictured a few posts above, as well as the IEC C17 to type I ungrounded described above, are almost certainly illegal in their respective countries.
The point is because the AC side is not directly connected to the DC side, there is almost no chance the user, who is touching the laptop, will be shocked with mains voltage (100-240v AC).
A grounded power supply would prevent them from being shocked with the ~20v DC charging the laptop, but it is debatable whether this is actually a problem (Apple clearly doesnât think so; they stopped including the grounded extension lead in the box with their computers).
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well, what Iâm trying to say is that the sockets are quite good, as they are both standarized and grounded. And more safe. Because they are usually pre-wired in the house, you canât change them as easily as you can change the plug (or whatever that is plugged into the wall).
Regarding the UK plugs that donât have ground, well, you can choose to not buy them