flush mount usb

[nigelmercier]

As well as the need to supply 2.1A for the higher power devices. If you are using iPads, iPhones etc they have a special voltage requirement on the data pins. Not all sockets adapters etc supply this

Yes. Providing the socket says it will work with an iPad, this voltage is provided by the USB power rails via resistors in the charger. Using a standard 5V power supply and a hub may not provide enough current, even with a powered hub.

However, if you really want to make your own, you could start with one of these:
http://www.amazon.co.uk/exec/obidos/ASIN/B0087ZAYTC/dolcetto-21

 

[prv]

Providing the socket says it will work with an iPad, this voltage is provided by the USB power rails via resistors in the charger.

Yep, but you do need to be careful because not all the adapters, including some of the high power ones, do this.

Pete

 

[ukmctc]

I bought the single adaptor from Maplin, £4.99. then opened it up, took the cigarette lighter negative and positive off, soldered two wires on put it all back together wired it to a switch, job done. Fully functioning 12v usb power socket wall mounted, with on off switch.

 

[Trop Cher]

I use something similar, these are very cheap:
http://www.amazon.co.uk/exec/obidos/ASIN/B005JCPZ22/dolcetto-21

Make sure whatever you get can do 2.1A

Thanks, ordered two, one for the boat and one for the car. £1.70 each including P+P!!!