Low-Pass
6-Pole
Appendix A
Butterworth
Theoretical Transfer Characteristics
1
Frequency Response
0
-20
-40
-60
-80
-100
f/fc
Amp
(dB)
Phase
(deg)
Delay
(sec)
(Hz)
0.00
0.10
0.20
0.30
0.40
0.50
0.00
0.00
0.00
0.00
0.00
-0.001
0.00
-22.2
-44.5
-67.2
-90.4
-115
.615
.617
.624
.637
.656
.685
0.60
0.70
0.80
0.85
0.90
-0.009
-0.060
-0.289
-0.578
-1.080
-140
-167
-198
-215
-233
.731
.803
.911
.970
1.02
2
2
3 4 5 6 7
0.1
3 4 5 6 78 1.0
10.0
Normalized Frequency(f/fc)
0.95
1.00
1.10
1.20
1.30
-1.88
-3.01
-6.17
-9.96
-13.9
-252
-270
-304
-331
-352
1.03
1.00
.845
.660
.518
Delay (Normalized)
2.0
1.0
0.0
1.40
1.50
1.60
1.70
1.80
-17.6
-21.2
-24.5
-27.7
-30.6
-368
-382
-393
-403
-412
.417
.345
.291
.251
.219
1.90
2.00
2.25
2.50
2.75
-33.5
-36.1
-42.3
-47.8
-52.7
-419
-425
-439
-450
-458
.193
.171
.132
.105
.086
0.15 2
3
4
1.5
0.1
5 6 7 8 91.0
3.00
3.25
3.50
4.00
5.00
-57.3
-61.4
-65.3
-72.2
-83.9
-465
-471
-476
-484
-496
.071
.060
.052
.039
.025
Normalized Time (1/f sec)
Step Response
6.00
7.00
8.00
9.00
10.0
-503
-508
-512
-515
-518
.017
-93.4
-101
-108
-115
-120
1.2
1.0
0.8
0.6
0.4
0.2
-0.0
.012
.0097
.0076
.0062
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).
0
1
2
3
4
5
Normalized Time (1/f sec)
Normalized Delay
Actual Delay =
Actual Corner Frequency (fc) in Hz
8
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