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Low-Pass
8-Pole
Appendix A
Butterworth
9
0.1
1.0
10.0
2
3 4 5 6 78
2
3 4 5 6 7
Normalized Frequency(f/fc)
-100
-80
-60
-40
-20
0
0.1
1.0
2
3
4
5 6 7 8 9
Normalized Time (1/f sec)
0.0
1.0
2.0
1.5
0.15
0
1
2
3
4
5
Normalized Time (1/f sec)
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
Frequency Response
Delay (Normalized)
Step Response
(sec)
Theoretical Transfer Characteristics
1
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.85
0.90
0.95
1.00
1.10
1.20
1.30
1.40
1.50
1.60
1.70
1.80
1.90
2.00
2.25
2.50
2.75
3.00
3.25
3.50
4.00
5.00
6.00
7.00
8.00
9.00
10.0
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).
Actual Delay =
Normalized Delay
Actual Corner Frequency (fc) in Hz
f/fc
(Hz)
Amp
(dB)
Phase
(deg)
Delay
-125
-135
-144
-153
-160
-76.3
-81.9
-87.1
-96.3
-112
-44.6
-48.2
-56.3
-63.7
-70.3
-23.4
-28.2
-32.7
-36.9
-40.8
-1.58
-3.01
-7.48
-12.9
-18.2
-671
-678
-683
-687
-691
-621
-629
-635
-646
-661
-560
-568
-586
-600
-611
-494
-511
-526
-539
-550
-0.001
-0.014
-0.121
-0.311
-0.738
0.00
0.00
0.00
0.00
0.00
0.00
-333
-360
-408
-445
-472
-185
-221
-261
-283
-307
0.00
-29.4
-59.0
-89.1
-120
-152
.023
.017
.013
.010
.008
.094
.080
.069
.052
.033
.253
.226
.174
.139
.113
.540
.448
.380
.328
.287
1.48
1.46
1.17
.873
.672
.956
1.04
1.19
1.29
1.40
.816
.819
.828
.843
.867
.903
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