USB sockets without built in converters

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Mikedefieslife

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Anyone seen any usb sockets that can be hooked up to a 5v source, rather than the things you get with built in 12v to 5v converters than never live up to their claimed current output.
 
Some devices require a reference voltage on the other USB pins (this is not hard to do, but is fiddly). Just supplying 5v is not enough to charge many devices.
 
I want a round wall/bulkhead mountable socket that I can just attach my own 5v wiring to. I could of sworn I saw a load of them a year or so ago when I was considering it.

Most of the 12v sockets I've seen and tried can only put out 2.4 amps max at 5v, and some of those can't even manage that despite claiming to.
 
Mikedefieslife said:
I want a round wall/bulkhead mountable socket that I can just attach my own 5v wiring to. I could of sworn I saw a load of them a year or so ago when I was considering it.

Most of the 12v sockets I've seen and tried can only put out 2.4 amps max at 5v, and some of those can't even manage that despite claiming to.
Click to expand...

The real limitation with regard to current supply from USB sockets if the power contect area and not only the electronics converting the 12vdc to the 5vdc.

This is what came up from google

USB 3.1 is backward-compatible with USB 3.0 and USB 2.0. USB 3.1 has three power profiles (according to USB Power Delivery Specification), and allows larger devices to draw power from a host: up to 2A at 5V (for a power consumption of up to 10W), and optionally up to 5A at either 12V (60W) or 20V (100W).Oct 26, 2016


https://www.google.co.za/search?ei=.....0.0..0.0.0.......0......gws-wiz.uXRGL0Ykn5Y
 
Mikedefieslife said:
I want a round wall/bulkhead mountable socket that I can just attach my own 5v wiring to.
Click to expand...

Are you planning to attach the power-signalling resistors as well? It won't matter how much current the wiring can supply if the device is limiting itself to 0.5A from an unknown source.

Pete
 
Well it's for a Raspberry pi. It doesn't have data lines going to the USB charging port.

It is perfect with my AC - DC 5v 3.5amp charger, so I'm looking to mimic that really. I could hack a USB cable to a DC-DC converter myself but I was looking for something more elegant.

My other option is to charge via the GPIO ports but theres no protection for over-voltage from the fuse, though I think the transient diode still trips at 5.2v - This is more of a faff though and involves drilling holes in my case though
 
Mikedefieslife said:
Well it's for a Raspberry pi. It doesn't have data lines going to the USB charging port.

It is perfect with my AC - DC 5v 3.5amp charger, so I'm looking to mimic that really. I could hack a USB cable to a DC-DC converter myself but I was looking for something more elegant.

My other option is to charge via the GPIO ports but theres no protection for over-voltage from the fuse, though I think the transient diode still trips at 5.2v - This is more of a faff though and involves drilling holes in my case though
Click to expand...

For a Pi a buck converter off ebay is a much better way to go IMHO. The Pi likes the voltage quite high, from memory mine was set to about 5.2v (Pi now powered from a hifiberry amp) with plenty power to spare for the transient peaks and to power a separate USB hub.
 
Mikedefieslife said:
Well it's for a Raspberry pi. It doesn't have data lines going to the USB charging port.
Click to expand...

Fair enough then. Just be aware that if you (or someone else) tries to charge say a tablet or smartphone from that port, which can source several amps of current but doesn't have the connections to say that it can, the rate of charge will probably be disappointing.

Panel-mount USB sockets are easily available all over eBay, not sure what it is you're asking for if not these.

Pete
 
Do not build in USB A sockets at this point. More and more devices are emerging with USB C connectivity. Presumably USB C sockets will emerge, but it is a lot more complicated. It took me a long time to find a 12V USB C socket that will actually charge properly. NB USB C is supposed to negotiate up to 20V if possible. If buying you need to look for the letters "USB C PD" where I think "PD" stand for "Power Delivery". I bought two that said they were PD but couldn't do it before I found one that did. Problem is, of course, that life was easier when you just had to supply 5V. If you have USB C a simple adaptor will provide USB A at 5V. I know that a horrible cigar lighter socket is not what you want but most of them have a C and an A socket. I'm going to dismantle one and turn it into a sensible socket after encapsulating all my bodgery in epoxy. The only one that I have found capable of charging a laptop is here: click. I have a phone and a laptop that can charge stonkingly fast with this. Of course you may decide to keep it simple, but you may regret it when you get your next phone. (I believe this post to be correct, but people more technical than me may refine/contradict it.)
 
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