Can we transfer power of electricity on to the laptop, through USB port?
DoubleO 7 asked:
I am doing a New Product Development project. And so, I was researching on a portable charging device (like a backup battery) which if plugged-in onto the USB of a laptop, would be able to give some battery life, at a time when there would be no access to sockets nearby.
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I am doing a New Product Development project. And so, I was researching on a portable charging device (like a backup battery) which if plugged-in onto the USB of a laptop, would be able to give some battery life, at a time when there would be no access to sockets nearby.
August 11th, 2009 at 3:55 am
Yes, you can, thats how things like iPhones and iPods charge.
August 12th, 2009 at 9:13 am
yes you can.
USB sockets have an output of +5V DC (5 volts direct current)
August 14th, 2009 at 4:12 pm
In short, no. The USB port has a 5VDC and Ground connection but you’re not going to charge the battery by adding an external power source to those pins - more likely you’ll blow the USB hardware. If you want to charge a laptop you’ll need to do it through the DC connection that the power brick normally connects to.
Sorry, there’s no shortcut to a universal charging connection - your product will need to deal with the myriad of different connections that laptops have. Of course you can expand your product line (and create an additional revenue stream) by providing separate adapters for the different connections you’d expect to have to support.
August 15th, 2009 at 1:25 am
USB is split into 4 internal cables, two that transfer data , and 2 for power. If you use only the power cables then you can send electricity to something such as a battery.
The cables are usually colored Red, White, Green, Black
Red (+) is for sending power (5V)
Black (-) is the grounding current
Green and white are for sending and receiving data
It get complicated beyond that though, as typically a USB port will transmit at most 5V, If you would like this to charge a battery or such, you may need to attach some transistors or resistors to tweak the ampage and wattage so you don’t blow the battery. And you also have to take into account the resistance of the wires.
So if you do your research correctly, a soldering gun and a trip to radio shack is all you’ll need.
If you want to charge a battery for a laptop like this, it will work, but it will charge very slow.