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LazMan
Premium
join:2003-03-26
canada

1 recommendation

reply to Edrick

Re: "Professional" Grade or High End USB Power

said by Edrick:

If no device can accept over 1.5A then how come so many chargers tout 2.1A for one port?

The -STANDARD- says no more then 1.5A - however, there are several devices (iPad probably being the most common) that are non-standard, and draw more....

lutful
... of ideas
Premium
join:2005-06-16
Ottawa, ON
kudos:1
reply to Edrick
There are official specs for both 3A and 5A rated "PD Cable Assembly" which only supply power and carry no data. Unfortunately, the spec does not provide any means to detect power carrying capability of the cable.

Imagine a charger allows 5A per port and is connected to a device which accepts 5A ... but some customer uses a vanilla USB cable which can't handle more than 1A.


cwnorris

join:2000-01-17
Longmont, CO
reply to tschmidt
Click for full size
My Asus tablet charger uses USB, but you need to have a USB 3.0 cable for it to charge at the higher rate.

»www.usb.org/developers/powerdelivery/

robbin
Premium,MVM
join:2000-09-21
Leander, TX
kudos:1
reply to Edrick
said by Edrick:

If no device can accept over 1.5A then how come so many chargers tout 2.1A for one port?

One word -- iPad


mackey
Premium
join:2007-08-20
kudos:14
reply to Kearnstd
It's all about the $$$.

The AC side is actually irrelevant for devices like this. Commercially sold devices need to worry about things such as UL and CSA approvals, so they can't just slap crap together. 5 amps is pushing it for those round barrel plugs; most of the time other connectors (which use multiple pins) are used for those kinds of power levels. So, they can either use more expensive connectors on more expensive wire (needs to be much thicker to overcome voltage drop), or they can run a higher voltage (say 12-18v) and add a buck converter in the hub/distribution block (additional parts = additional $$$$). All for a niche product that isn't going to move that many units (99% of consumers won't know the difference between this more powerful but more expensive power distribution system and the el cheapo on the shelf right next to it - they're both "USB chargers" after all).

/M


tschmidt
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join:2000-11-12
Milford, NH
kudos:9
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reply to Edrick
said by Edrick:

If no device can accept over 1.5A then how come so many chargers tout 2.1A for one port?

I have no idea.

/tom


Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA
reply to tschmidt
If no device can accept over 1.5A then how come so many chargers tout 2.1A for one port?


tschmidt
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join:2000-11-12
Milford, NH
kudos:9
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reply to Edrick
USB has the notion of a unit load. Early this was 100/500ma, USB 3 increased it to 150/900 ma at 5 Volts. The purpose of having two levels is the device must power up at low value and then request permission to switch to higher consumption. All upstream ports must be able to supply at least low power on a per port basis with high power being optional. This is what makes USB powered and unpowered hubs feasible and guarantees the bus will not become overloaded.

There is a special option for charging ports, that operate as power transfer only, no data transfer. They are limited to 1.5A, the upper limit of the connector.

There is a higher voltage option, kind of like Ethernet PoE, I don't know status or how well it has been received.

That is why you are not going to see 5V 2A USB per port capability. Are you sure any of the devices you have draw more then 900 ma or 1.5A? If so I'd be surprised.

/tom

Kearnstd
Space Elf
Premium
join:2002-01-22
Mullica Hill, NJ
kudos:1
reply to Edrick
I am surprised at the lack of such hardware, I know computer ports are limited because of the motherboard limits but something plugged into the wall would have no trouble supplying even 5A to several ports since the 5A in i think 5 VDC does not directly translate to 5A on the AC side of the device.
--
[65 Arcanist]Filan(High Elf) Zone: Broadband Reports


UHF
All static, all day, Forever
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join:2002-05-24
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reply to Edrick
I've been hoping to find something similar, but for hardwired automotive use. Would be nice to charge ipod, ipads, cellphones, gps, etc. So far I've only found one or two outlet units that plug in to a cigarette lighter plug.

Maybe we need to design our own and make a Kickstarter project


BlueMist

join:2011-01-24
Cookeville, TN
reply to Edrick
You might want to check out something like »www.satechi.net/index.php/satech···sb-3-hub.

You may need to get USB 2 to USB 3 adapter cables depending on what you want to plug into it but you will be future proofing at the same time by going to a USB 3 standard hub. You can attach this to something and use it as a USB hub/charger or use it stand-alone as just a USB charger.

This hub comes with it's own 5a power supply to supply it's many ports. Having the 3 power switches to turn off banks of 3 plugs each is also a nice feature or you can ignore it.

Mister_E

join:2004-04-02
Etobicoke, ON
Reviews:
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reply to Edrick
Optionally, there are AC Outlets with built-in USB charge circuits available. Most appear to be USB standard @ 500mA, but I've seen 1A and 2A versions as well.

»www.google.ca/search?q=usb+ac+ou···HOqYHADg

Belkin (as well as others I'm sure) sell Surge Protectors with USB Charging ports built in as well (some are smaller travel units):

»www.belkin.com/us/Products/Power···/WSPWRSP


Camelot One
Premium,MVM
join:2001-11-21
Greenwood, IN
kudos:2
reply to Edrick
I have been looking for the same thing for awhile now. The best I have come up with is a 4 amp (total) box, split over 6 plugs, or the really high end ($500+) USB distribution systems.

You would think with as many high draw USB devices as most people own, someone would have come up with something by now.


Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

"Professional" Grade or High End USB Power

I'm looking for basically a multi port power hub that I can just plug into the wall and have multiple at least 2A ports to plug in many devices that need charging. I have a lot of USB devices that just have batteries in them like GoPros, External Battery Packs, Ipads, etc... and need a central device to plug them all into.

Ideas?