- #1
peasngravy
- 72
- 6
- Homework Statement
- Design and PSPICE model a bandpass filter of ‘Sallen and Key’ topology, having the following characteristics:
fo = 3.3khz
Q=2.2
Verify your design by means of a Bode plot.
- Relevant Equations
- V2/V1 = -1/ (2R1/R2) + jwCR1 + 1/(jwCR2)
I have the above transfer function for this filter design
The transfer function becomes
which then becomes
Now when I try to use this transfer function to plot a bode plot, I always end up with negative terms which i can't get the square root of
For example, at 1hz, where
w = 6.283
R1 = 1705
R2 = 33000
C = 6.43nF
I end up with
Is anyone able to explain where I am going wrong with this?
Thanks
The transfer function becomes
which then becomes
Now when I try to use this transfer function to plot a bode plot, I always end up with negative terms which i can't get the square root of
For example, at 1hz, where
w = 6.283
R1 = 1705
R2 = 33000
C = 6.43nF
I end up with
Is anyone able to explain where I am going wrong with this?
Thanks