HI ;-)
I was going through op-amp.... I have certain doubts.....
1) Concept of virtual ground
2) Output swing
can anybody please answer this..... thanks a lot in advance :smile:
I/p impedance of an opamp is very high and hence very little current flows thru it's inputs and hence very little voltage drop occurs at i/p.Hence if one of it's i/p is grounded ,since voltage difference b/w two i/ps will be very less we can assume other one of the i/p also to be at ground and hence giving rise o term 'virtual gound'.
I/p impedance of an opamp is very high and hence very little current flows thru it's inputs and hence very little voltage drop occurs at i/p.Hence if one of it's i/p is grounded ,since voltage difference b/w two i/ps will be very less we can assume other one of the i/p also to be at ground and hence giving rise o term 'virtual gound'.
The high input impedance of the opamp inputs is NOT the reason for the "virtual ground concept". Remember: This concept applies also to the Current-feedback topology with a very low negative input impedance.
The background is the very high loop gain that very often can be assumed to approach infinity.