1. Active Filter It is phasor time again

2. Active Low Pass Filter Amplification: R F /R S low pass factor 1/(1+j  R F C F ) Cut off frequency:  R F C F =1 R F /R S =10, 1/R F C F =1

3. Figure 8.24, Active high-pass filter R F /R S =10, 1/R F C F =1

4. Figure 8.26, 8.27 8-11 Active bandpass filter Figure 8.26 Normalized amplitude response of active bandpass filter Figure 8.27

5. Let’s build an integrator Let’s start with the following insight: We need to somehow convert voltage v I to current

6. First try…use resistor But, v 0 must be very small compare to v R, or else When is v 0 small compare to v R ? For good integrator  RC >> 1

7. There’s a better way…

8. Op Amp Integrator Examples: 8.6, 8.7 Drafting problem

9. Op Amp differentiator Triangle wave to square wave