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Do you need all 4 pins on a usb for it to work? Answered

I need to know if you need to have all the pins on a usb female connector for it to work. (I'm making a usb charger)


Here's the pinout : You only need the red and black power connections for a charger, but bear in mind that you can only draw 100mA from it this way.  More than that and your computer will shut down the port and report an over-current condition.

You can get up to 500mA out of a USB port but to do that you need to request it via negotiation on the data lines - well outside the scope of a simple charger.

Depending on the device your charging you only need the red and black. Some devices such at the iPhone and iPods have to see a voltage across the data pins before it will start charging. Other smart phones do the same thing.

i cant select yours as the best because it is a reply
But yours and AndyGadgets are the best

Could you tell me specific devices other than just the ipod,etc.

What devices are you trying to cover with this charger? Have you tried charging them with just the power leads?

If your looking for this charger to work across many devices then you may as well build in the extra resistors on the data lines so you have universal compatibility.

yep you need all 4 pins to work coz it happened to me and i lost all my homework and got detention at school. maybe it may work in a different computors USB socket . SIMPLE IDEAS ARE THE BEST .just go with the flow.

Technically no, but check out the copious number of Instructables posted on building USB chargers. Find some that do it each way (with and without the data lines) and decide what is best for your application.