input and output impedence of opams

Replies

• 

  Harshad Italiya

  as per my knowledge there is no load connected so it should be zero.. because you see ideally Zout should be as low as possible near to Zero.
  
  Zout= Rload/1+Aol.
  
  In this case no RL so it should be zero.
• 

  cranky

  is there any other way or some kind of analysis we can do?
• 

  shreyasm89

  yes there is...actually if you refer to any good book on OP_AMPS they will give you the detailed analysis. From wat I know, for finding Ri u should ground one i/p terminal of the op-amp and then analyse the the remaining part. As for o/p impedance, short the i/p and connect the source at the o/p. Then do analysis of the circuit by considering i/p as zero. you have to consider the current flowing through the series o/p resistance. Actually when u refer the books they'll give u the equivalent circuit of an op-amp which if u go through once, calculating both the impedances will be child's play.
• 

  cranky

  thank you😀..will get back to you.