Appendix A
November, 2000

 


Low-Pass
3-Pole
Butterworth


Theoretical Transfer Characteristics
 
f/fc   Amp   Phase   Delay1
(Hz)   (dB)   (deg)   (sec)
 
 
 
 
 
 
 
0.10
 
0.000
 
-11.5
 
.320
0.20
 
0.000
 
-23.1
 
.325
0.30
 
-0.003
 
-34.9
 
.335
0.40
 
-0.018
 
-47.3
 
.350
0.50
 
-0.067
 
-60.3
 
.372
 
 
 
 
 
 
 
0.60  
-0.198
 
-74.1
 
.398
0.70
 
-0.483
 
-88.9
 
.423
0.80
 
-1.01
 
-104
 
.436
0.90
 
-1.85
 
-120
 
.428
1.00
 
-3.01
 
-135
 
.398
             
1.10
 
-4.43
 
-149
 
.352
1.20
 
-6.01
 
-160
 
.303
1.30
 
-7.65
 
-170
 
.257
1.40
 
-9.31
 
-179
 
.217
1.50
 
-10.9
 
-186
 
.185
             
1.60
 
-12.5
 
-192
 
.158
1.70
 
-14.0
 
-198
 
.137
1.80
 
-15.4
 
-202
 
.119
1.90
 
-16.8
 
-206
 
.105
2.00
 
-18.1
 
-210
 
.093
             
2.50
 
-23.9
 
-223
 
.056
3.00
 
-28.6
 
-231
 
.038
3.50
 
-32.6
 
-237
 
.027
4.00
 
-36.1
 
-241
 
.021
5.00
 
-41.9
 
-247
 
.013
             
6.00
 
-46.7
 
-251
 
.009
7.00
 
-50.7
 
-254
 
.007
8.00
 
-54.2
 
-256
 
.005
9.00
 
-57.3
 
-257
 
.004
10.0
 
-60.0
 
-259
 
.003

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).

     
    Normalized Delay
    Actual Delay =  
      Actual Corner Frequency (fc) in Hz

 

 



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