Passive LC ladder
Passive LC ladder with computed response and explicit circuit realisation.
Development preview. Check the assumptions below before relying on a result. Calculations run in your browser.
How it calculates
Butterworth prototype: gk = 2 sin[(2k−1)π/(2n)]
Chebyshev prototype: γ = sinh(asinh(1/ε)/n); g1 = 2a1/γ; gk = 4ak−1 ak/(bk−1 gk)
Terminated response: GT = 4 Rs RL / |A RL + B + Rs(C RL + D)|²
Assumptions
- g-values are computed, not copied from tables. Even-order Chebyshev ladders generally require unequal terminations; the required load is reported separately from the actual load. Shunt-first uses the dual ladder and reciprocal load ratio. Loss plots use the actual entered source/load and cascaded ABCD matrices. Components are lossless; ESR, inductor self-resonance and PCB parasitics are omitted.
Worked example
These are the calculator's default inputs. Change any input above to recalculate.
Inputs
- Prototype
- butterworth
- Prototype order
- 4
- Response
- lowpass
- Cutoff / ripple-edge frequency
- 1000000 Hz
- Chebyshev passband ripple
- 0.5 dB
- Source termination
- 50 Ω
- Actual load termination
- 50 Ω
- First element
- series
Results
- Order
- 4
- Prototype load termination
- 50 Ω
- Transducer insertion loss at corner
- 3.0103 dB
- Low/high passband insertion loss
- -1.92865e-15 dB