Filter lab
RF filter designer
Design 50 Ω Butterworth low-pass, high-pass, and band-pass ladders from first-order LC sections up to 7th order networks.
All calculations assume lossless components and 50 Ω source/load. Real coils and capacitors may need trimming after measurement.
Multi-section Butterworth ladders favour tightly matched capacitors and inductors—select high-Q parts and re-check tolerance before soldering.
Real-world coils need the right core material and turns. Use the Toroid Inductor Calculator to pick a mix and winding that meets your inductance and current goals.
After soldering, sweep the filter on the LC Resonance Analyzer or a VNA to confirm the cutoff and ripple match expectations. Small component trims often tighten the response.