06 August, 2011

Belkin 4 port USB hub / more iPhone charging experiences

I wanted something to charge several USB devices at once, and adaptors only go up to 2, so I tried a USB hub instead. I got a Belkin hub, which has 4 ports and is powered (meaning it comes with its own power adaptor).
The good news is, yes, it supplies power if you just plug in the adaptor and don't connect it to a computer. I can charge my Kindle and LED message board.
(Not a picture of the board charging, just to show you what it is) The bad news is, it doesn't charge the iPhone/iPad (without a computer)! This is a summary of the situation:
iPhone: charges only if computer and power adaptor connected
iPad: does not charge at all
The hub doesn't have any indicator lights, which is disappointing for such an expensive hub. The Logitech powered USB hub had individual lights for each port.

After searching online, I found the situation is as I expected: the hub needs some "intelligence" for the iPhone to charge, just like the iPod Touch.
http://nttup.wordpress.com/2008/06/07/usb-device-charging-un-mystified/
In short, the device asks the hub, "hey, can you supply 500mA?", and the hub has to reply for the charging to go. The good thing is, it isn't an Apple thing, they're just following the USB rules here. A solution would be to modify the hub: http://carlhutzler.com/blog/2009/07/28/usb-hub-as-an-ipodiphone-charger/ but this would disable data transfer, and I'm not going to do that to my new hub. Another solution would be to modify the cable, and in fact I saw a charging cable on ThinkGeek that probably does that. It's quite expensive though, and I'd rather buy a wall adaptor.

With so many people wanting to charge their devices, it's odd no company has made and advertised a USB hub that can charge without a computer. I also wonder about the many USB charging devices, like the power sockets with built in USB ports, if they can supply 500mA?

Summary of USB chargers:
Dumb - charges: Kindle. Probably because it only needs 100mA.
  • Belkin USB hub (without computer)
  • No brand USB adaptor

Intermediate - charges: iPod Touch, iPhone, NOT iPad
 (Not sure if the last 2 can charge the iPad, so putting them here)

Ultimate - charges iPad and everything else (so far)
  • MacBook Pro USB port
  • iPod power adaptor (the one that comes with iPhone and Apple's universal travel kit)
  • iPad charger
  • Taiyo travel charger
The last one is a curiousity.
The front says "Taiyo TH-252 USB". I bought it because it was a travel adaptor and had 2 USB charging ports, so I only needed to bring this while traveling. It happily charges my iPhone and iPad, which now I know to be no mean feat! At first I thought this was a simple charger, and the devices weren't picky. The main problem with this adaptor is it seems loose in the socket - if you push it in, it springs back a little. The same with plugs in its own socket. However, I think its charging capabilities more than make up for this.

2 comments:

  1. This help me tons. Thanks for the detailed information.

    ReplyDelete
  2. That's great, that's what I'm trying to do with this blog.

    ReplyDelete