I am trying popped a transistor while trying to power my raspberry pi from a bread board. I have a 12v battery pack that I am going to use to power my raspberry pi and some servo's. Yesterday I checked the voltage coming out of the output voltage from one of the power rails on the breadboard and it was 5 volts. When I attached my raspberry pi it popped one of the transistors on the board that I used to convert the 12volt to 5 volt. BTW the odd thing is that after frying the transistor it was outputting 10 volts to the rails. Luckily it did not cook my pi :) . I am using a B+ and connected the first 5v pin and the 3rd pin which is ground on my pi. Counting pins only on the outside of of the header and not the board layout. Should I have used the second 5v (pin 2 on the outside of the header). BTW what is the second 5v pin for? I only have one 5v on my model B.
Any ideas would help as I am new to electronics and don't want to fry another board. I apologize if this is not the right forum maybe there is a better stackexchange site but I figured I would start here.
Here is the breadboard power supply that I was using. http://www.amazon.com/gp/product/B00GWIL0MQ/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
Here is the power supply I was using. http://www.amazon.com/gp/product/B007RQW5WG/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1
Found another option on amazon and it appears the mb102 max output is 700ma and the pi can pull 1.5A current so this is probably what happened.