|
Design LC Filters (V 3.0 May 16, 2010 )
Now with bandpass, bandstop and frequency response plots!
This web based application allows the user to design simple radio frequency filters
with inductors and capacitors. These filters are most effective between 50 kHz and
500 mHz. Below 50 kHz active filters are usually more cost effective and above
500 mHz strip lines are generally used.
Formulas and tables used in this program are from Electronic Filter Design Handbook by Arthur B. Williams.
Open source code is here.
The user selects the basic type (Lowpass or Highpass), number of poles, 3 DB cut off
frequency and the I/O impedance. The application
generates the parts values for three response shapes: Butterworth, Bessel
and 0.1 DB ripple Chebyshev. Two different configurations with schematics
are generated. The frequency response plots are approximations which assume perfect components and construction. Real world results with not be as good. The Bessel plots are only accurate to 2x the cutoff frequency (1/2 for highpass).
The user selects the basic type, Bandpass or Bandstop, number of poles, 3 DB bandwidth and the I/O impedance. The application generates the parts values for three response shapes: Butterworth, Bessel
and 0.1 DB ripple Chebyshev. Two different configurations with schematics
are also generated.
Note: These filters are sensitive to stray capacitance and inductance and the Q of the components. Keep in mind that capacitors have series inductance and inductors have parallel capacitance which in some cases can be very significant.
This program underwent major additions and changes on 16 May, 2010. Please report bugs on my contact page.
|