# Is it possible to make a usb charger to power multiple devices?

I was thinking how nice it would be to have a single wall plug with multiple (4-6) USB ports that would be capable of supplying enough power (at 5v) to charge say an iPad, smartphone, bluetooth headset etc. simultaneously at full capacity. But I haven't been able to find such a thing anywhere.

So I am contemplating making one. I don't have any knowledge of electronics and only a rudimentary knowledge of electrics (I can wire a plug) and would appreciate it if someone could tell me how viable this would be from an electrical/electronic point of view. Assuming it is feasible, I'd also like to know whether the work required to make such a thing could be done by an enthusiastic beginner.

Of course if someone can recommend somewhere I could buy such a device I'd happily buy it instead ;-)

• It is interesting how today we rely on low power voltages rather than 220/110 supplies. I have seen USB wall plugs with 2 ports on it rated at 1A- not more. With a bit of DIY you could make it into 6/8 your self and avoid buying a HUB – Piotr Kula Oct 3 '12 at 12:34
• DIY - Buy a 3 x 2 socket USB wallplugs. Make openings for extra ones in one of them or in a complelty new wall plate. Transfer the USB sockets- solder them up to the power supply/transformer (or upgrade it to a higher AMP rated on) using another transformer/ voltage regulator. Hmm. Maybe it s cheaper to buy a HUB- But esthetically you will have that "built" into your wall. nice and clean. You want me to build you one? – Piotr Kula Oct 3 '12 at 14:55
• No- But I am going to try to make one. I have done other similar things with plugs; its not that difficult and looks good if you keep it uniform and square holes ;) – Piotr Kula Oct 4 '12 at 8:40
• See addition to my answer. A 7 port hub and a 5V 5A psu sound like a good start. – Russell McMahon Oct 4 '12 at 12:22
• Eh - Sorry when i read wall plug and you simple wiring skills i though you meant like the plug in the wall(face plate gang) Did not realise you just wanted a simple high power charger. Any way I did link to a 2.1A iPad compatible (generic ones don't charge iStuff- yay! Thanks Steve! RIP ) – Piotr Kula Oct 4 '12 at 21:42

A 5 Volt power supply of whatever rating suits plus some USB port hardware is the main requirement.

Just increasing the power feed to a cheap USB hub is probably the cheapest easiest way. Some existing current limiting hardware MAY need to be bypassed.

5V, 5A should be ample. As you are located on Nowhere, OK you should have no problem picking one up locally.

Here's a bargain powered USB hub on ebay UK. 4 GBP for a 7 port hub wit power supply. Power supply is rated at 1A, 5V, so

ebay UK 5A 5.5V psu GBP7.80 buy now - from Hong Kong BUT free economy delivery.

5V 5A GBP8.60 free delivery HK

12/24V to 5V/5A - Shenzhen free delivery SMPS care

Two of these internal UK GBP 16 each :-(

• Thanks for your comments. Can I safely assume that I won't be able to damage my kit by doing this? Apologies if this is a facile concern, but I am mostly clueless on these matters. – 5arx Sep 15 '12 at 8:50
• @5arx - Damage is always possible in life, BUT iy you provide +5V and ground where +5V and ground power usually goes you should be OK. Shorting a 5A 5V supply should not be too spectacular BUT the 25 Watts+ that it is capable of can burn wiring and tracks if invited to. Connect it properly and it should be OK. – Russell McMahon Sep 15 '12 at 10:10
• Since he mentioned up to 6 devices and mentioned iPads (which are 2 A), I would consider a 12 A supply instead of the 5 A you suggested. – Brian Carlton Sep 26 '12 at 22:05
• Not having much luck tracking down such a device. Would appreciate a link ... – 5arx Oct 3 '12 at 15:44
• Will those charge iPhones/Ipad's and all the rest of Apple wierdness? I posted a 4 port 2.1A hub that supports iStuff. (OP wants to charge his iPad) None of those will charge iStuff, sadly. – Piotr Kula Oct 4 '12 at 21:38

EDIT- Ok I know you said in UK- But i found these on e-bay dot com or direct

Possibly easier and cheaper than doing it the DIY way. It does not include power addpeter so you would still have to wire it to AC and connect all the USB ports correctly to suply power.(maybe dissect an 2.1A multi port "apple" charger and put it in there)

-Original

It seems the max is 2 USB ports per faceplate.. Why? Dunno...

• I found this though that can give you max 3.
• But if you want you can DIY them and possibly get 6.

4. Measure how you can fit 2 USB sockets in 1 blank plate. Cut them out(using a square file and a cordless drill to start off)(+ elbow grease)
5. Use some sort of epoxy on the inside to hold the usb plugs nice and snug. Don't be shy- be sure to scratch smooth surfaces like the pvc so the epoxy will bond better. Also clean any metal with some alcholo to remove oil residue from your fingers
6. Wire them to a 5V supply of 2A atleast

I cannot guarantee that iPhone/iPad devices will just work. Those damn things need some sense signal or something so it will require more research into that. But a Raspberry Pi will work fine or HTC, USB LED's, etc, etc ...

Good Luck :)

• Many thanks for the comprehensive answer. Sadly I think that putting together this sort of thing safely is going to be beyond my limited knowledge of electronics. I'll keep looking ... – 5arx Oct 4 '12 at 11:26

You must be aware of a usb hub.Just take a reasonable adapter that outputs up to 5v and connect it to one end of your usb hub.
NOTE: current rating is must to be checked before implementing any such design else you'll see smoke. Normal USB current values are safe for this purpose

Update:-

You can purchase powered usb hub at

• This will likely achieve only low-rate charging, not the higher rates provided by dedicated device chargers. – Chris Stratton Sep 15 '12 at 3:39
• Yes this is a major problem with IPad users ,they keep on complaining about the 2A current rating requirement that slows down charging with usb port. – perilbrain Sep 15 '12 at 3:48
• Exactly. My current hardware (various macs and pcs) will at best only trickle charge my phone (HTC) and iPad. Both report that there is insufficient power and both will eventually run out if used while plugged into on board USB ports. Apparently contemporary motherboards can supply the higher voltages required but I am reluctant to upgrade my laptop just for this. – 5arx Sep 15 '12 at 8:46
• If only they'd kept firewire charging. Sigh. – Optimal Cynic Oct 4 '12 at 14:31
• If only they'd kept FireWire. – 5arx Oct 4 '12 at 21:52

A USB charger is not just a simple 5v supply and connector. The charger has to tell the device how much power there is. I believe that normally they put a resistor between the data lines. But for the full 2.1amps there is some odd system of voltages on the data lines indicating power that seems to be hard to find an official reference for.