Second-Order RLC Filter Designer
Description
This MicroSim lets you design a second-order RLC filter by setting the resonant frequency \(f_0\) and quality factor \(Q\). The Bode plot, bandwidth, peak gain, and component values all update in real time.
Filter types (series RLC, output tap changes):
| Type | Output across | Behavior |
|---|---|---|
| Low-Pass | C | Passes low frequencies; peaks near \(f_0\) when Q > 0.707 |
| High-Pass | L | Passes high frequencies; symmetric peak behavior |
| Band-Pass | R | Passes a band centered at \(f_0\); peak = 0 dB always |
Key parameters:
| Parameter | Formula | Notes |
|---|---|---|
| Bandwidth | \(BW = f_0 / Q\) | Narrower for higher Q |
| Damping ratio | \(\zeta = 1/(2Q)\) | \(\zeta < 1\) → underdamped (peak) |
| Peak gain (LP/HP) | \(\approx 20\log_{10}(Q)\) dB | Only when Q > 0.707 |
Component values are calculated for a fixed L = 10 mH: [C = \frac{1}{\omega_0^2 L}, \quad R = \frac{\omega_0 L}{Q}]