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I wish more things were USB-C powered. I am currently traveling and among the things I have with me are two Raspberry Pi devices. One with a touch screen, the other with a 5TiB SATA HDD in an enclosure. One of the RPi devices uses 5V power, the other 12V. Both have the same kind of barrel connector.

Guess who arrived at an AirBnB a couple of days ago, tired and just wanting to get things quickly unpacked and set up. And guess who forgot which was which of the 5V and 12V powered device and plugged the 12V power cord into the 5V device.

That’s right, this guy :(

So now my RPi powered device with the 5TiB SATA HDD does not power on anymore, and for all I know plugging the 12V power supply into it may have even broken the circuit board of the HDD, in which case it will be very expensive to get my data back as HDD circuit replacement is outside of my set of skills.

I wish all of these electronic I carry just used USB-C instead.




You can buy USB-PD trigger boards and make most stuff USB-PD powered. For instance: https://vi.aliexpress.com/item/1005006068684294.html


Caveat: I bought one of these boards (labeled "ZYPDE" "YZXSTUDIO") that supposedly had soft programming capability--you hold down a button for the right amount of time and it programs it to produce 5v, 9v, 15v, etc the next time you turn it on. But it never worked. It always came up in a mode where you had to push the button the right number of times to get the voltage you wanted. I like the idea of DIP switches or soldered jumpers much better.


This one can be more useful in certain situations, because you can much more easily change its configuration on the fly with the DIP switches.

https://www.aliexpress.us/item/3256805068086690.html


Isn’t this the reverse? Providing USB-C rather from a power source rather than powering from a USB-C supply.


No, the connector you see is the receptacle, not the cable side. USB-C cables are hollow ovals, the tab is on the device.

You'd take this thing or something like it, set the DIP switches/solder bridges/jumpers appropriately, get a few 2.1x5.5 (or appropriate) barrel jack to screw terminal adapters, wrap it and a couple wires in heat shrink and hot glue it to the back of your HDD/RPi/etc, and have a USB-C plug to power your HDD adapter.


Well this is amazing, thanks! Do you know if it can output whatever I want by shorting a jumper, or are these fixed when you get them?

EDIT: Oh damn, this doesn't do 5V, which is what I need the most :(


It looks like you just solder the pads for the maximum voltage you want, and some of the pictures demonstrate what 12v being soldered looks like.

And there are definitely 5v options, like these:

https://www.aliexpress.us/item/3256805818718384.html

https://www.aliexpress.us/item/3256805815622101.html


Thanks, I ended up buying something very similar to that!


USB defaults to 5V, so depending on how much current you want to draw you might not even need a trigger module.


USB-C defaults to "off", so a 5V PD trigger would be a sensible product. It just needs a couple resistors, no chip.


There’s no such thing as 5V PD unless you mean 5V 5A, fyi. PD is an optionally supported standard of USB-C and the resistors are not part of PD, just the standard USB-C spec.


You are technically correct, in that using resistors to trigger 5V would fall under "USB Type-C Current" rather than "USB Power Delivery".

But what would you call such a product, other than "5V PD trigger"?


5V USB-C board


You're right, I guess I might as well just get some straight breakouts for a USB-C for the 5V case, but then I'll be limited to half an amp, which is probably fine for my uses, I guess.


USB-C supports up to 3A without PD, using only (I believe) resistors/voltages to communicate the limit.

That's what many simple early USB-C chargers used to do in order to supply 15W without full PD signalling.


I didn't realize that, thanks!


No, but this is:

https://fpx.oxplot.com/


Electric Shaver. Every single manufactures, and even across their own product line all uses a slightly different charger.

I am not even a USB-C for everything person. But if we could have 80%+ of Consumer electrics that uses less than 30W to use USB-C would be a great start.


I would pay a good chunk of money for a BIFL device that took usb-c, and had support for attacking a shaver head or toothbrush head, and had reasonably priced head replacements for both.


I've seen adds for a new Philips multi-attachment one but it doesn't say if it's USB-C or not. There's finally usb-c powered electric toothbrushes. Unfortunately they all seem to be "low powered".


The ironic part is that barrel jacks tried to solve your problem by being completely non-standard to the point of absurdity.

There are so many different kinds and sizes of barrel jacks that when I was trying to order one that matches a cable I had, I eventually rage quit out of exasperation when even when finally finding and ordering some that matched the specs, they didn't fit, lmao. I now power everything with XT30/60 connectors.


The other problem with barrel jacks is that there's current going through them all the time; iirc USB doesn't have anything or only the default 5 volt until there's been a transfer of information where the two sides indicate they can handle higher voltage/power.

Source: 14 year old managed to jam the barrel jack into his laptop's HDMI port and fucked the whole device.


Every time I need to buy a new barrel type power supply I'm always looking for one with a pack to different tips. Now I've got a pile of adapter tips, I can plug just about any supply into any device.


My problem with barrel jacks (besides the myriad diameters) is that there's also different lengths and tip shapes, like how the insulated part of the center fits.

I used the wrong tip (non original) for a network switch, and even though it felt like a perfect fit and worked, it must have been a poor enough fit to start arcing. The plug was completely melted, though luckily the gear was undamaged.


That could also have been a polarity issue. Some are center positives, others center negative.


Mine is loose enough that it won't charge without a bit of foil jammed in there, and arcing is a non-issue. How much power does it draw?


Just buy a bag of 5.5x2.5 connectors with panel mount sockets. XT30/60s are going overboard and pretty much everything now under 19v that uses barrel coax is either 5.5x2.5/2.1 or 3.5x1.5.


Do XT30/XT60 connectors actually have a standard yet?

I still have issues buying them from "real" distributors and manufacturers. I still can't seem to cough up an actual datasheet.

For a while, some of them had a habit of arcing and catching on fire, as well. Not a big deal when doing attended, high impact stuff like racing or robots. However, that's a BIG problem when using them for unattended power.


I think it's less of a standard and more genuine connectors made by Amass vs. knock offs. They even have a patent apparently.

XT60 spec: https://www.tme.eu/Document/2d152ced3b7a446066e6c419d84bb460...

XT30 spec:

- female https://www.tme.eu/Document/f2d0830114aabe6ea8d4bb128e962790...

- male https://www.tme.eu/Document/7d9d972ae3468777f69ec2ee99897652...


It's a shame that there aren't better low cost 2pos connectors. I'm partial to the LEMO style push-pull connectors or the Neutrik style twistlock connectors for "real projects" e.g..when someone has paid me money for their thing to work and keep working.


You might look at Anderson power pole connectors. They are quite popular in the HAM community, but I came upon them doing FIRST robotics mentoring.

They are configurable to more than two poles and can be keyed by changing the orientation of the poles.

The small size ones go to 45A DC and are easily crimped and assembled.


Well aware of the Anderson connectors. They're big, ugly, and have no ingress protection. They have their place.


Back when there were electronics stores, you could just go and buy a tip that you could try out at the store, and match it to a power supply that had the right voltage and wattage.


Can still do that at 2nd-hand stores. May not be the greatest electrical efficiency.

Don't forget to match polarity if your device requires DC and doesn't have a bridge diode. (Looking at you SNES!).


In addition to the PD trigger boards, you can actually get short cables with USB-C ports on one end and barrel jacks of specific voltages. I use a 12V one for my soldering iron (love it) and have a couple 5V ones for various networking gear.

No DIP switches, no ability to change what they output, just rock-solid functionality assuming you can get the exact tip you need for your device you probly can from aliexpress).

One caveat: In my experience all these things (cable and PD boards alike) will output 5V if the charger does not support whichever voltage (5V when you want 9V, 12V, or 20V, for example). I’d much rather they put out nothing in those cases. Hopefully the next generations will.


To be fair, this is fully on you.

Raspberry Pi boards already come with USB-C; you shouldn't have chosen to downgrade that with barrel plug cases.


I think they were probably using ready made kits. And most Raspberry pi models don't have USB C. It was introduced with V4.


> probably using ready made kits

Yep


Problem here is that the connector doesn't mean everything: https://community.ui.com/questions/AI-THETA-USB-cable-Hub-to...


The links says:

>This part of community is for Early Access Users


Something that should go USB-PD is electric bicycles.


Battery pack that big will be better served by a larger connector for power (500Wh battery can sink more than basically any USB-C source can supply),

But the big reason is it's just a big object, and using a little tiny wire and plug on a big object that can fall over is just asking for damage. There's a reason 120V plugs are the size they are, and it's not ampacity. Big connectors for big objects. Small connectors for small objects.

That being said a dual role sink -source controller on a motorized bicycle battery pack would be super convenient for charging phones on the go etc


Well, at this time every e-bike battery has a one-off charger, at best shared with other models of the same brand. It would be cool if they were a little more uniform. That would make it easier to host e-bikes in the bike room of an office or apartment building.


I think you're correctly observing that there's a hole in the available smart charging specifications around the power levels needed for motorized bikes. USB-PD is perfect for most small devices, electric cars and larger have their own protocols, but 0.5-1 kWh batteries are left in the cold. (xkcd 927:1-3)


USB PD is 20v max. I think most electric bikes are 24v or 48v


It goes up to 48 V these days!

That's still "only" 240W, i.e. not nearly enough to charge electric bicycles. The other direction would still be nice, i.e. for faster charging of phones mounted on the handle bar.


The whole line of Specialized e-bikes charge at 42V, 2 to 4A. USB-PD 3.1 would be more than enough for an e-bike.


Oh, I wasn't aware that the charging power was so low!


240 w would charge most e-bikes in 2 hours


Caveat, bikes are outdoor devices, it's probably better to have wireless charging on an e-bike.


Many phones have been waterproof for a while now, and I've used at least one that's told me that I had moisture in the charging port, with charging being paused while that was the case.

I'd rather take my chances during the few times I need to really charge my phone in the rain over the inevitably slower charging speeds and inefficiencies that go with wireless charging, especially when the power source is also a battery.



Interesting. Unfortunately, that is not quite enough to charge a 48v li-on battery. You need something like 52v.


https://www.amazon.com/dp/B0BGFC77M6

5v, 9v, 12v, 15v, 20v - selectable with all kinds of adapters.

I had a motorized massage gun that had a 9v barrel connector, this thing worked perfectly. I can also use it to charge a 12v usb-c tablet I have that won't work with normal usb-c PD.


>may have even broken the circuit board of the HDD, in which case it will be very expensive to get my data back as HDD circuit replacement is outside of my set of skills.

That's absolutely on you for not having a backup of a HDD that gets moved and tossed around and replugged constantly.

That HDD dying suddenly is an inevitability that will have happened sooner or later.


The problem is having a reliable and secure backup system.

- Carrying an extra HDD with me is not feasible. It weighs extra, and if my luggage gets lost they both get lost and we are back to 0 copies left.

- I have copies of copyrighted material that I’ve bought. I’m not gonna sync that to the server I rent because they might mistake it for piracy.

- My computer at home has less storage, so I can’t sync to it while traveling because there is not enough space left at home. I bought the 5 TiB HDD while traveling.

- I think it’s pretty darn silly that electronics are so unreliable, that having one HDD is not enough. It bothers me a great bit in fact.

- I’m not gonna put my files in the cloud either.

- Sync problems are a PITA to resolve.

- A lot of places that I go, internet is slow and unreliable. In many cases if I were to ZFS send a snapshot of my HDD over the internet with a couple GiB of new data it would likely lose the connection mid transfer and I’d have to retry over and over and over and I just don’t have time nor energy for that.

So it’s not as easy as you make it out to be.


>- Carrying an extra HDD with me is not feasible. It weighs extra, and if my luggage gets lost they both get lost and we are back to 0 copies left.

Why are you not keeping a copy at, say, home? Even if it gets old between backups, having some data is better than complete data loss.

>- I have copies of copyrighted material that I’ve bought. I’m not gonna sync that to the server I rent because they might mistake it for piracy.

Why are you backing up to a location not under your ownership?

>- My computer at home has less storage, so I can’t sync to it while traveling because there is not enough space left at home. I bought the 5 TiB HDD while traveling.

You have monies and time to rent a server, buy a huge HDD on the road, procure gadgets, but none for basic upkeep back home?

>- I think it’s pretty darn silly that electronics are so unreliable, that having one HDD is not enough. It bothers me a great bit in fact.

The fickle nature of electronics has nothing to do with this. If something is important to you, you keep multiple copies in case one gets destroyed. Because one day, some deity in the sky is going to decide you will suffer today.

>- I’m not gonna put my files in the cloud either.

See response to backing up to a rented server.

>- Sync problems are a PITA to resolve.

There are solutions that could help you, because many people have walked that path.

>- A lot of places that I go, internet is slow and unreliable. In many cases if I were to ZFS send a snapshot of my HDD over the internet with a couple GiB of new data it would likely lose the connection mid transfer and I’d have to retry over and over and over and I just don’t have time nor energy for that.

If you accrue so much data while on the road that a proper backup scheme is impractical, you absolutely should still duplicate it on another HDD to at least reduce the risk of data loss.

Backing up is ultimately a question of whether the time lost recovering from data loss is more expensive than implementing and performing a backup scheme. It's a question of motivation, not difficulty.




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