Hi, this might sound like an obvious question, but I don't know the answer. I'm going to the U.S. and Canada for a week on Sunday and I'd like to take my laptop and my Nintendo DS + charger and mobile + charger. I have an adapter I take to Europe with me that changes the plug from 3 pins to 2 pins but I don't think it does anything to the voltage. What will I need when I go to the U.S. and Canada please? Thanks in advance!