Do amplifiers work with AC signals?

Replies

• 

  Jeffrey Arulraj

  Hey my friend AC signal can be amplified by the amplifier using an external DC source
  
  You can amplify the current of a signal maintaining the voltage using either emitter follower or source follower
  
  Do post the current rating you need and your input we can help you more in identifying the solution
• 

  Ramani Aswath

  zaveri

  now supposing an A.C current has to be amplified leaving the voltage unchanged, then what should be the power input to the amplifier ?

  That is what an audio amp does.
  High Current Amplifiers
• 

  pratap singh, upendra

  yes an amplifier definitely works with an ac signal.
  
  now coming back to whether it can amplify a current or not, let me tell you that there exists a class of amplifiers termed as current controlled current source. This means that if the amplifiers are pictured as a two port network(one input port and one output port) then such an amplifier takes current signal and produces its amplified version in the same dimensional domain(i.e the output is still a current).
  
  remember biasing of the amplifiers is done to merely make it "an active device". without biasing an amplifier remains only a piece of semiconductor with some electrical connections. It is the biasing that paves the way for transistor action to take place within it. The biasing does not govern the signals an amplifier can amplify, it however governs the way in which the amplifier will amplify the signal.