Which wires in a usb wire are the positive and negative for power?

I need to use a wireless router for a bit to download gps maps for offline use (no data plan) but i can’t find the power cord for the router, it needs 5V and 2A, and i have a usb plug adapter that puts out 5V and 2A, so if i splice a usb wire which i am willing to sacrifice which wires do i use?

Also will it put out the full 2A or does it need some sort of signal from the device to do so?

you can use a DMM to probaly determine which color wires the V+ & V- connections are the power, but in the plug its usually the two outside pins as seen here: >> http://atmega32-avr.com/wp-content/uploads/2012/11/USB-pinout.jpg

or: http://www.electroschematics.com/wp-content/uploads/2010/01/USB-cable-wiring.png

its usually the red & black for power, and the green & white are data.

thanks, the wire is being chopped in 3…2…1 :slight_smile:

Are you modding a USB cable because the wire isn’t thick enough to put out the amperage?

Red = pos, Black = neg
green and white are the data wires

Its running, i am downloading gps maps over wifi using an ml102 and one of my flashlight batteries to power the router!

You can always use one of those portable power packs…but they are limited in the output
I have an OSHPark project where a guy designed one that is capable of pushing 3.6A

Careful with that miller…it can only push a certain amount of current before the output chips get too hot and smoke

You turned your charger into a portable power pack…how cool is that! :wink:

i hope it does not get smoking and i hope it has low battery voltage shutdown, i’ll need at least 15 mins of operation

Beautiful thing about those millers

Remember those el-cheapo portable power units that people were looking at (I bought 5 of em)…this is a MUCH better version of those…built in a case where you can easily remove the battery…think a strip of packaging tape or kapton wrapped around an 18650 and the body [to keep the battery from falling out]…viola…portable power unit, without the tape…it becomes a very solid TP4056 based 18650 battery charger I am thinking this is the route I am going to go from now on…no more needing to get those ones playing chinese roulette…this one is a KNOWN good setup and it won’t break the bank!

mine only charges to 4.11V and its replacement charges to 4.05V so not so grand

on the plus side it had low battery protection, at 3.58 volts it stopped running, my thing was only 25% downloaded so i’m running it straight off a 5V2A usb wall plug

This image is incorrect and is coming up on Google Image searches involving USB wire colors.

Green is D+
White is D-

Doesn’t matter the PCB or what direction the cable is going, D+ (or DP) and D- (or DM) are always the same colors.

If possible, please edit the post with a correct diagram so it doesn’t continue to come up on Google.


A guy trying to help