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Gaussian Lowpass Filter Prototype Element Values
(to 6 dB & to 12 dB)

The table below lists prototype element values for the normalized lowpass function, which assumes a cutoff frequency of 1 rad/sec and source and load impedances of 1 Ω. Either an input capacitor (top reference line in table) or an input inductor (bottom line in table) can be used.

Convert values to other cutoff frequencies, impedances, and to highpass, bandpass or bandstop using the denormalizing equations here.

See the online filter calculators and plotters here.

Complex Gaussian poles are here.

Denormalization of values is here.

Prototype filter schematic - capacitor input

Capacitor Input

Prototype filter schematic - inductor input

Inductor Input

Gaussian to 6 dB

Order C1 L2 C3 L4 C5 L6 C7 L8 C9 L10
3 0.3655 0.9032 2.269              
4 0.4153 0.8634 1.142 2.264            
5 0.4300 0.9132 1.109 1.195 2.335          
6 0.4280 0.9319 1.152 1.176 1.275 2.301        
7 0.3975 0.9082 1.150 0.212 1.248 1.267 2.347      
8 0.4117 0.9142 1.167 1.225 1.297 1.245 1.320 2.306    
9 0.3848 0.8606 1.132 1.199 1.306 1.263 1.309 1.269 2.378  
10 0.4139 0.8897 1.160 1.205 1.329 1.275 1.361 1.249 1.360 2.281
  L1 C2 L3 C4 L5 C6 L7 C8 L9 C10

Gaussian to 12 dB

Order C1 L2 C3 L4 C5 L6 C7 L8 C9 L10
3 0.2691 0.8202 2.229              
4 0.2275 0.5888 0.9586 2.241            
5 0.2452 0.5751 0.7681 1.013 2.266          
6 0.2635 0.6055 0.7617 0.8421 1.055 2.255        
7 0.2473 0.5845 0.7555 0.8127 0.8840 1.049 2.281      
8 0.2688 0.6149 0.7891 0.8404 0.8837 0.8973 1.083 2.251    
9 0.2455 0.5571 0.7357 0.8012 0.8073 0.8616 0.9225 1.051 2.297  
10 0.2762 0.6115 0.7907 0.8416 0.9086 0.8923 0.9270 0.9104 1.102 2.240
  L1 C2 L3 C4 L5 C6 L7 C8 L9 C10