What pins put out voltage and what is the maximum amount?

I know the 3v3 puts out 3.3v and If I am correct you can program pin 1 and 5 to put out voltage.
What is the max amount of volts that they can put out?
Where can I find out how to program these pins to put out the max amount of volts that a pin can put out

@Hugo

http://devwiki.electricimp.com/doku.php?id=electricimpapi:pin:configure

Writing a value from 0 to 1 will output a voltage from 0V to the imp’s operating voltage ( usually 3.3V). You can get the exact voltage with hardware.voltage().