Author Topic: Usb Power Injection Fix For Usb Devices  (Read 5059 times)

VirtusRex

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Usb Power Injection Fix For Usb Devices
« on: June 26, 2007, 12:45:56 pm »
Hey guys,

I've been looking around for a way to power my USB wireless NIC without a powered host when I came across this article. It's a gadget someone created that supplies power to USB devices, which might come in handle if you wanted to power say now a USB keyboard.

What do you guys think???

Here's the link:

http://tabletblog.com/2006/01/usb-power-injector-2.html

Later,

VirtusRex

jpmatrix

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Usb Power Injection Fix For Usb Devices
« Reply #1 on: June 26, 2007, 12:54:55 pm »
Quote
Hey guys,

I've been looking around for a way to power my USB wireless NIC without a powered host when I came across this article. It's a gadget someone created that supplies power to USB devices, which might come in handle if you wanted to power say now a USB keyboard.

What do you guys think???

Here's the link:

http://tabletblog.com/2006/01/usb-power-injector-2.html

Later,

VirtusRex
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whow
looks like little dangerous for our Z, not ? besides i don't like the 9V battery
why not look for battery powered usb hub or battery powered usb device?

see here:
[a href=\"http://jpmatrix.livejournal.com/]http://jpmatrix.livejournal.com/[/url]
« Last Edit: June 26, 2007, 01:00:24 pm by jpmatrix »
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kkazakov13

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Usb Power Injection Fix For Usb Devices
« Reply #2 on: June 27, 2007, 02:39:12 am »
Well, it's not dangerous, as long you know what you're doing. I have made (thanks to lougi600) 4xAA power supply for my Z, and would prefer to use the same to power the devices that require more power.

Unfortunately, here in Bulgaria I cannot find where I can buy USB mini male/female jacks

Anyone knows an online store to order?
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gromituk

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Usb Power Injection Fix For Usb Devices
« Reply #3 on: July 01, 2007, 05:40:18 pm »
Rather a naive implementation, using a 5V linear regulator with a 9V supply, which will be very inefficient (i.e. eating batteries unnecessarily).  The advice with 78xx regulators is also to connect a decoupling capacitor close to input and output to avoid oscillation, and this is not done here.

I'd just go with four NiMH rechargeable cells in series, giving 4.8V or so - close enough.  It would be wise to wire a fuse into the circuit.

louigi600

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Usb Power Injection Fix For Usb Devices
« Reply #4 on: July 02, 2007, 04:30:20 am »
Quote
Rather a naive implementation, using a 5V linear regulator with a 9V supply, which will be very inefficient (i.e. eating batteries unnecessarily).  The advice with 78xx regulators is also to connect a decoupling capacitor close to input and output to avoid oscillation, and this is not done here.

I'd just go with four NiMH rechargeable cells in series, giving 4.8V or so - close enough.  It would be wise to wire a fuse into the circuit.
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A fuse ... hum : if you want a fuse there it better be a fery fast blow one because the ones inside the Z are already fast blow ... so if you want to be sure that it blows before the ones inside the Z it must be faster (and possibly very close to the max rate absorbed by Z).
A normal wire fuse will be pretty useless for this pourpouse ;-)

For anyone intrested in making wierd stuff for their Z: have a look in my home page under the "ZElectronics" section ... there is some material to get ideas from ;-)

I also saw somewhere that it's possible to change a resistor in the USB OTG voltage regulator of the C1000 (and maybe also C3x00) so that it can drive safely 500mA: this would allow you to connect any single USB device that is within the USB power specifications. The firs time I open my C1k I'll probably make that modification (and document it on my home page).
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