1. 1 More on Op Amps Discussion D12.1

2. 2 Ideal Op Amp 1) The open-loop gain, A v, is infinite. 2) The current into the inputs are zero.

3. 3 Ideal Op Amp with Negative Feedback Golden Rules of Op Amps: 1.The output attempts to do whatever is necessary to make the voltage difference between the inputs zero. 2.The inputs draw no current.

4. 4 Non-inverting Amplifier Closed-loop voltage gain

5. 5 Unity-Gain Buffer Closed-loop voltage gain Used as a "line driver" that transforms a high input impedance (resistance) to a low output impedance. Can provide substantial current gain.

6. 6 Inverting Amplifier Current into op amp is zero

7. 7 Question Find i 0

8. 8 Question Find i 0

9. 9 Differential Amplifier Current into op amp is zero

10. 10 Differential Amplifier

11. 11 Summing Circuit

12. 12 Integrator

13. 13 Active Filter

14. 14 Active Filter What will the net gain be at  HI if you put two such filters in series?

15. 15 Current-to-Voltage Converter

16. 16 Photodiode Circuit At 50 mW