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Reply With QuoteWhat do you intend to plug into those USB ports?
2A is enough to fry nearly any USB device you plug into it, considering they are looking for a fraction of that amount.
I was searching for a solution to an issue with a project I'm working on and stumbled across this forum. Very cool stuff here, and although my project doesn't concern in-vehicle computers I was wondering if you could give me some pointers.
What I want to do is power 3 USB ports with a 12v car battery. Each USB port will provide 5v2a of power, which rules out some of the well-known USB devices like the Carnetix P5USB, which only provides the standard .5a per port. So what's the most straightforward way to deliver the desired amount of power to the USB ports from the battery? I don't have much experience with electronics, so ideally I can find a way that doesn't involve microchip programming or lots of soldering.
One thing I looked at was this compact power supply:
http://www.mini-box.com/picoPSU-90;j...4Pa38Ta38Ra3j0
If I cut the female ends off of 3 USB cords and connected their 5v wires to the 5v sockets on this power supply, would I get 5v USB power? With 3 5v ports attached to a 90 watt power supply, does that mean that each port would have 6a available? I plan to have only the USB ports connected to the car battery and nothing else, so I don't need most of the advanced features found on devices like the Jopel Designs ACPPS (http://jopeldesigns.com/acppsv1.html).
If this would work or you can think of something else that would I welcome your comments.
USB is 5Volts and 0.5Ampere, and if you connect any USB devices to your planed set up... You'll fry about anything.
I would also think twice about running 2A on wires designed to run 0.5A
As DarquePervert is asking.. What are you going to use this for.. Perhaps easier to give you a propper anwser then
correct me if i am wrong..but electrical components only fry if you give them more voltage.. all components draw as much amps as they require.. so if a hub can give 2 amps that means this is the maximum power it can offer
I'll be running some battery chargers that I specifically know can handle the 2a current. And there are USB port devices out there that deliver 2a current, for instance:
http://www.usbpoweradapter.net/usb-d...er-adapter.htm
These AC power adapters are favored for running high-amp charging devices. I'm looking for something that can do the same without being tethered to an outlet.
If you got a source with 2A, and a device that consumes 0.5A, does not burn anything, the device use only 0.5A and 1.5A in abundance in the power supply, Always maintaining the voltage 5 volts.Originally Posted by Crinos
USB is 5Volts and 0.5Ampere, and if you connect any USB devices to your planed set up... You'll fry about anything.
I would also think twice about running 2A on wires designed to run 0.5A
As DarquePervert is asking.. What are you going to use this for.. Perhaps easier to give you a propper anwser then
just remember, the tiny little wires in a usb cord are also designed around the 0.5 amp spec... so you could still fry something.
if you need more than 0.5 amps of current, you should really look into using a different type of connector/wire in the project.
Well, I know my device can handle the 2a, so the only other issue is to make sure the female USB port it plugs into can deal with it. Maybe I could find a place to get just the female USB socket and solder on a thick and sturdy power wire myself. But would the idea I described above with the tiny power supply work?
what you need is a voltage regulator:
http://search.digikey.com/scripts/Dk....dll?Selection
and maybe a 2A fuse to limit the current.
and you're good to go!
Electrical stuff usually only take the current it needs, except when there's a short circuit, then it'll draw a ridiculous amount of current, which will fry the component. So there's usually current protection in place to protect that from happening.
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