Low-Pass
6-Pole
Bessel
Appendix A
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
-15.5
-31.0
-46.5
-62.0
-77.4
.430
.430
.430
.430
.430
.430
-0.029
-0.116
-0.261
-0.465
-0.728
0.60
0.70
0.80
0.85
0.90
-1.05
-1.44
-1.89
-2.15
-2.42
-92.9
-108
-124
-132
-139
.430
.430
.430
.430
.430
2 3 4 5678
1.0
2 3 4 567
10.0
0.1
Normalized Frequency(f/fc)
0.95
1.00
1.10
1.20
1.30
-2.70
-3.01
-3.68
-4.44
-5.29
-147
-155
-170
-186
-201
.430
.430
.429
.428
.426
Delay (Normalized)
1.0
0.5
0.0
1.40
1.50
1.60
1.70
1.80
-6.23
-7.29
-8.46
-9.74
-11.1
-216
-232
-246
-261
-275
.422
.416
.401
.393
.376
1.90
2.00
2.25
2.50
2.75
-12.6
-14.2
-18.3
-22.6
-26.7
-287
-300
-328
-351
-369
.357
.335
.279
.228
187
2
3 4 5 6 7 89
1.0
0.15
1.5
0.1
3.00
3.25
3.50
4.00
5.00
-30.7
-34.5
-38.1
-44.7
-55.9
-385
-398
-408
-426
-449
.156
.131
.111
.083
.052
Normalized Time (1/f sec)
Step Response
1.2
1.0
0.8
0.6
0.4
0.2
-0.0
-0.2
6.00
7.00
8.00
9.00
10.0
-65.2
-73.2
-80.1
-86.2
-91.6
-465
-476
-484
-490
-495
.036
.026
.020
.015
.013
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).
Normalized Delay
Actual Delay =
0
1
2
3
4
5
Normalized Time (1/f sec)
Actual Corner Frequency (fc) in Hz
3
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