Raspberry Pi Forums

Ok so ive decided im just going to make my own usb power supply using this :https://www.modmypi.com/usb-diy-connect ... cro-b-plug

I was wondering if someone could explain clearly which of the 5 tabs need to be give the power line, and which needs the ground.

Also, should i be supplying 5v through the usb or is 6v safe?

thanks

The supply specifications for the Pi are the same as a standard USB device: 5V +/- 5%, which gives 4.75V min to 5.25V max. The Pi may survive higher, but any USB peripherals connected to the 5V line might not.

For the plug, I'd connect it to a Pi (wthout any power) and test for continuity/resistance between the solder tags and the test points. The Gnd connection should show 0 Ohms (or a tiny value) and the +5V one will show slightly higher if the fuse is in the circuit.

rpdom wrote:The supply specifications for the Pi are the same as a standard USB device: 5V +/- 5%, which gives 4.75V min to 5.25V max. The Pi may survive higher, but any USB peripherals connected to the 5V line might not.

For the plug, I'd connect it to a Pi (wthout any power) and test for continuity/resistance between the solder tags and the test points. The Gnd connection should show 0 Ohms (or a tiny value) and the +5V one will show slightly higher if the fuse is in the circuit.

The power lines are the outer two of the five of the mini-USB plug/socket, but to be sure of the polarity the advice above is good. (Getting the polarity wrong on a Model A or Model B is usually fatal. The B+ is more forgiving.)

And to pick a nit, the term 'charger' is inappropriate. Although devices intended to be used as chargers for other devices are often used as power supplies for RPi's, when so used they are not functioning as chargers.