Low-Pass
4-Pole
Appendix A
Theoretical Transfer Characteristics
1
f/fc
Amp
Phase
Delay
(Hz)
(dB)
(deg)
(sec)
0.00
0.00
0.00
.336
0.10
-0.028
-12.1
.336
0.20
-0.111
-24.2
.336
0.30
-0.251
-36.3
.336
0.40
-0.448
-48.4
.336
0.50
-0.705
-60.6
.336
0.60
-1.02
-72.7
.336
0.70
-1.41
-84.8
.336
0.80
-1.86
-96.8
.335
0.85
-2.11
-103
.334
0.90
-2.40
-109
.333
0.95
-2.69
-115
.332
1.00
-3.01
-121
.330
1.10
-3.71
-133
.325
1.20
-4.51
-144
.318
1.30
-5.39
-156
.308
-166
1.40
-6.37
.295
-177
1.50
-7.42
.280
-187
1.60
-8.54
.263
-195
1.70
-9.71
.246
-204
1.80
-10.9
.228
1.90
-12.2
-212
.211
2.00
-13.4
-219
.194
2.25
-16.5
-235
.158
2.50
-19.5
-248
.129
2.75
-22.4
-259
.107
-267
3.00
-25.1
.089
-275
3.25
-27.6
.076
-281
3.50
-30.0
.065
-291
4.00
-34.4
.049
-305
5.00
-41.9
.031
6.00
-315
.021
-48.1
7.00
-321
.016
-53.4
8.00
-326
.012
-58.0
9.00
-330
.009
-62.0
10.0
-333
.008
-65.7
Bessel
Frequency Response
0
Amp (dB)
-20
-40
-60
-80
-100
0.1
2
1.0
2 3 4 5 6 7
10.0
Normalized Frequency(f/fc)
3 4 5 6 78
Delay
(Normalized)
1.0
Delay (sec)
0.5
0.0
0.1
0.15 2
1.0
1.5
Normalized Time (1/f sec)
3
4
5 6 7 89
Step Response
1.2
1.0
0.8
0.6
0.4
0.2
-0.0
-0.2
0
Step Response (V/V)
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
1
2
3
4
Normalized Time (1/f sec)
5
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2
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