Discussion in 'General Electronics Chat' started by banzai, May 27, 2014.

  1. banzai

    Thread Starter Member

    Jan 3, 2014
    hi guys

    I got got a 2n3055 transistor that i want to wire, my problem is that i got limited experience with transistors and circuit boards (still learning tho). I am going to supply the tranaistor with 12v to run a small dc fan, my question is what voltage should be applied to the base and do i need to hook up a resistor to the base.

    Thanks in advance :)
  2. crutschow


    Mar 14, 2008
    The base-emitter junction looks like a forward-biased diode so its ON voltage is about 0.7V so you definitely need a resistor in series with the base to limit the current. The resistor value should be selected to provide a base current of about 1/10th of the current that the load (fan) requires.