USB-C for charging

Airline friendly 12s4p p42a
same discussion of 99wh and under packs here
Flying with battery


Can I ask you the inside of you wonderful little box ?
I you have schematic and picture I would love to see them all !

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I can only guess, but I would assume there’s a USB PD consumer negotiator IC (for example STUSB4500) on the USB-C side, which is then fed to a boost converter. Then for current and voltage control he either has a MCU inside that reads the trimmer positions for the set voltage and current and then controls/biases the boost IC via the MCU to get set those values for it. The MCU could also be used to read the output voltage and current and display them on the 7-segment display.

Alternatively there could be just chinese modules inside that are doing those functions independently. The metal enclosure gives a good heatsink for cooling.

My 2 cents.


was just thinking this.

apparently it is possible to have more than one port.
then use this thing


As I understand it…while Power Duo mode can handle up to 10A it is only via a single port. I don’t think you can parallel USB ports for this. That is essentially short-circuiting two ports together.

The mentioned two power paths are inside the controller, two sets of FETs that can be both turned on at the same time to reduce the resistance and allow more current to flow for the same amount of heat.

I love the idea but unfortunately Power Duo mode also requires compatible USB PD controllers (e.g., TI’s TPS65987D) on both ends of the cable that are configured for that mode. It also requires a very good 5A-rated USB-C cable and connectors in order to handle the 10A of current.

But using 5A rated USB cable and connectors, even if meeting the 2x overcurrent capability required for getting certification, is not a great idea IMO. I would recommend using custom cables and connectors.

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aww miss u jeff :hugs:

huh I did not hear this name before only “USB C PD trigger module”
confusing because it sounds very close to the XY-PDS 100W PD step down power delivery module.

PDS100 QC4.0 QC3.0 Type C DC12 28V 100W Step Down Mobile phone quick charger module for Huawei SCP/FCP Apple PD Qualcomm|Integrated Circuits| - AliExpress
PDS100 QC4.0 QC3.0 Type C DC12 28V 100W Step Down Mobile phone quick charger module for Huawei SCP/FCP Apple PD Qualcomm|Integrated Circuits| - AliExpress

slightly different, skinner version

this big sucker

one last thingy

So then we need to pick out some good boost converters. I really want to try paralleling multiple PD inputs to a boost module.

random link

I have no idea what I am looking for.

I used this one before, big too huge to go inside a board… hmm actually not sure how much sense making an external PD booster would make but good proof of concept.

Once you have multiple USB adapters (not sure you can parallel these), stepping down and converting the AC-mains voltage, and a big boost-converter to step everything back up again are you gaining anything over just using a standard AC-mains to pack-voltage charger box?

The few percent loss of power through the USB adapters and again through the boost-converter can add up. Though I guess it’s not a real issue when using the AC-mains. If you were using a pack as a type of powerbank then it could be a problem.

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1: ability to charge slowly using whatever usb C PD charger, if you built step-up into the board. Even if you do not have one they are universal if you borrowed one.

2: ability for that PD charger to be battery powered if you so desired, and easily using that same PD battery for all you other devices.


Whoa….verrrry good points!
Limited capacity though for #2 when board charging unless carrying a big pack? Great idea for #1.

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Yeah or there’s some qiaomi phones that charge at 120w maybe it’s available on aliex

I think most of the time that you’re using multiple PD sources they’ll likely be different models, and that could cause some problems. Even good designs are often mains referenced to a small extent, like loosely coupled through a feedback resistor or capacitively coupled through parasitics. This could be an issue if you have 2 sources that are referenced to mains, but not at the same potential relative to mains. If they are connected in parallel you’re effectively shorting together the difference in the common reference.

It could probably be done with some more thoughtful input protection, and maybe it’s not really an issue at all, but it doesn’t seem completely plug and play

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sorry I made that giant blob response where I almost wanted to make a thread dedicated to the PD sources. So I was really looking for a solid one to get to try all this with, paralleling and stuff.

I am looking mostly at this as it is the cheapest and I found a nice video showing it off:

That would be using a battery or maybe 24V server psu so they would have identical V DC input.

does not seem to need contact with the case for cooling so I was thinking the easy way to make a compact dual PD would be to stack two of these in a case with some airflow.


Are their numbers on the (two?) bigger chips?
If you can read them we can look up some info on whether their outputs can be paralleled. I’m hopeful but, TBH, doubtful this can be done.

I was confused by the AliExpress page for that module as one image seems to say that you can only get the 20V/5A 100W PD output by using a >87W PD input. But if you already have a 100W PD adapter to power this module’s input then why would this module be needed?

But, another image shows the barrel jack being used for the input and a USB tester showing the PD output of the module being 20V/5A. :thinking:

I’m definitely confused about what that module can do but I’m very interested in seeing what can be done.

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That is prob some bad translation. It seems to me as long as you give it like 21+V then it can put 5A at 20V out. I am curious about when we will see these buck USB C PD modules with faster shipping on ebay/amazon, does not seem to be a large amount of people using them but when they are only in china it would be that way.


Wait…are we missing something here?

Why not just use an AC-mains powered 100W PD adapter connected to a USB pass-through tester that can force the adapter to 20V/5A? Then send that to the boost charger.

No need to have an intermediate stage to convert voltages.


they are the layer of intercompatibility that makes the battery bank for your phone also for the board.
It’s possible that confusion has occurred.

It is true that if you have a battery bank powering a USB C PD system that the battery powering the PD buck could instead direct output be connected to the boost inputting to the boards battery. wow mouth full there
It would really depend on the design of the battery bank PD system and your boards buck input.

I see your point.
I would hope that the tester module would handle compatibility issues but having that additional USB stage definitely takes care of it. Thank for your patience in dealing with my questions. :slightly_smiling_face:

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huh now I am kinda thinking about how it would be a fun challenge to make a booster pack/USB PD powerbank that supercharges.

A 8S2P with A123 cells and charge the sucker over 50A or something. Then it can more slowly keep the big pack charged. 130Wh is not much, maybe 3P but getting too chunky then.


48v @ 5amps it seems.

Just boost to 50.4v for 12s or buck to 42 for 10S and you’re golden (if you trust your bms)