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🎛️ RC Low-Pass Filter Calculator

Calculate cutoff frequency with detailed error propagation from component tolerances.

Component Values

Resistor

Capacitor

📈 Cutoff Frequency (fc = 1 / 2πRC)

Nominal Value
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⚠️ RSS Error (Statistical)
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⚠️ Worst-Case Error (Conservative)
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How It Works

RC Low-Pass Filter Formula

Cutoff Frequency: fc = 1 / (2πRC)

Time Constant: τ = RC

Error Propagation

RSS Method (Statistical): Δfc/fc = √[(ΔR/R)² + (ΔC/C)²]

Worst-Case Method (Conservative): Δfc/fc = |ΔR/R| + |ΔC/C|

Example

R = 10kΩ ±5%, C = 100nF ±10%
Nominal fc = 159.15 Hz
RSS Error: ±11.2% (√(0.05² + 0.10²))
Worst-Case Error: ±15.0% (0.05 + 0.10)

The RSS method is more realistic for production tolerances. The worst-case method is conservative and useful for critical designs.