Appendix A
August 1999

 


Low-Pass 8-Pole Butterworth


Theoretical Transfer Characteristics
f/fc Amp Phase Delay1
(Hz) (dB) (deg) (sec)
       
0.00 0.00 0.00 .816
0.10 0.000 -29.4 .819
0.20 0.000 -59.0 .828
0.30 0.000 -89.1 .843
0.40 0.000 -120 .867
0.50 0.000 -152 .903
       
0.60 -0.001 -185 .956
0.70 -0.014 -221 1.04
0.80 -0.121 -261 1.19
0.85 -0.311 -283 1.29
0.90 -0.738 -307 1.40
       
0.95 -1.58 -333 1.48
1.00 -3.01 -360 1.46
1.10 -7.48 -408 1.17
1.20 -12.9 -445 .873
1.30 -18.2 -472 .672
       
1.40 -23.4 -494 .540
1.50 -28.2 -511 .448
1.60 -32.7 -526 .380
1.70 -36.9 -539 .328
1.80 -40.8 -550 .287
       
1.90 -44.6 -560 .253
2.00 -48.2 -568 .226
2.25 -56.3 -586 .174
2.50 -63.7 -600 .139
2.75 -70.3 -611 .113
       
3.00 -76.3 -621 .094
3.25 -81.9 -629 .080
3.50 -87.1 -635 .069
4.00 -96.3 -646 .052
5.00 -112 -661 .033
       
6.00 -125 -671 .023
7.00 -135 -678 .017
8.00 -144 -683 .013
9.00 -153 -687 .010
10.0 -160 -691 .008
 

Notes:

  1. Normalized Group Delay:
    The above delay data is normalized to a corner frequency of 1.0Hz.
    The actual delay is the normalized delay divided by the actual corner frequency (fc).



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