RLC Circuit Calculator
Calculate resonant frequency, Q-factor, impedance, and damping characteristics for RLC circuits
Calculate RLC Circuit Parameters
Resistance value in the RLC circuit
Inductance value of the inductor
Capacitance value of the capacitor
RLC Circuit Analysis Results
Resonant frequency: f₀ = 1 / (2π √(LC))
Q-factor: Q = (1/R) × √(L/C)
Input values: R = 0.00 Ω, L = 0.000e+0 H, C = 0.000e+0 F
Circuit Quality Analysis
Example Calculation
Radio Tuning Circuit
Application: AM radio tuning circuit
Resistance (R): 30 Ω (coil resistance)
Inductance (L): 25 mH (tuning coil)
Capacitance (C): 50 μF (variable capacitor)
Circuit Type: Series RLC for frequency selection
Calculation Results
f₀ = 1 / (2π √(LC))
f₀ = 1 / (2π √(0.025 × 0.000050))
f₀ = 1 / (2π √(1.25×10⁻⁶))
f₀ = 1 / (2π × 1.118×10⁻³)
f₀ = 142.35 Hz
Q = (1/30) × √(0.025/0.000050) = 0.745
RLC Circuit Applications
Radio Tuning
Variable capacitor circuits for selecting specific radio frequencies from the spectrum.
Audio Filters
Bandpass and notch filters in audio equipment and crossover networks.
Oscillators
LC tank circuits in radio transmitters and signal generators.
Q-Factor Guide
Q < 0.5
Overdamped - No oscillations
Q = 0.5
Critically damped - Fastest response
0.5 < Q < 1
Underdamped - Some overshoot
Q ≥ 1
Good quality - Suitable for resonant circuits
Quick Reference
Understanding RLC Circuits
What is an RLC Circuit?
An RLC circuit is an electrical circuit consisting of a resistor (R), inductor (L), and capacitor (C) connected in series or parallel. These circuits are fundamental building blocks in electronics, exhibiting natural resonant behavior where energy oscillates between the magnetic field of the inductor and the electric field of the capacitor.
Key Characteristics
- •Resonant frequency depends only on L and C values
- •Quality factor Q determines circuit selectivity
- •Resistance R controls damping and bandwidth
- •Phase relationship between voltage and current varies with frequency
Circuit Behavior
Design Considerations
- ✓Higher Q provides better frequency selectivity
- ✓Lower resistance increases Q-factor
- ✓Bandwidth is inversely proportional to Q
- ✓Component tolerances affect frequency accuracy
Series RLC Circuit
- • Impedance Z = R + j(ωL - 1/ωC)
- • Minimum impedance at resonance (Z = R)
- • Maximum current at resonant frequency
- • Voltage across L and C can exceed input voltage
- • Used in bandpass filters and tuned amplifiers
Parallel RLC Circuit
- • Admittance Y = G + j(ωC - 1/ωL)
- • Maximum impedance at resonance
- • Minimum current from source at resonance
- • Current through L and C can exceed input current
- • Used in tank circuits and oscillators