Myke Predko

Neat little Hack for the TWR-ELEV to use USB Chargers for Power

Discussion created by Myke Predko on Feb 12, 2013
Latest reply on Feb 14, 2013 by Monica Arvizu

Running out of USB ports on my PC and having a plethora of USB wall-wart chargers, I wanted to be able to use them. 


When I plugged a mini-USB cable into them and then into my TWR-ELEV (primary) PCB, I couldn't get any power to the TWR.  After a bit of research, I found that if you short together the DP and DM pins of the USB socket, the device becomes a "Dedicated Charging Port" (DCP which can be sourced up to 1.5A) and is recognized by the charger (and PCs) as such. 


The DP and DM lines are Pins 2 & 3 of the socket and with a steady hand (and probably a microscope) they can be shorted together on the TWR-ELEV board (if you look at the schematic, these lines along with the identification line (ID) on Pin 4 are floating). 


This is NOT recommended for any other boards but for the two TWR-ELEV primary PCBs I have, it works quite nicely and eliminates the need to plug into a PC for power.