LC Resonance Tuning
CI
CircuitSim
·
Created May 10, 2026
·
Updated Jun 30, 2026
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Details
Components
2
Schematic
Yes
Simulation
AC sweep
Copies
Not copied yet
About this circuit
A variable capacitor tuning an LC resonant response.
Circuit notes
LC Resonance Tuning
Application
Use this circuit as a simplified radio tuning or narrowband filter example.
Design Context
A source and series resistor excite a shunt LC tank so the resonant response appears at Vtank.
Expected Behavior
The AC response changes as the variable component setting changes, shifting the resonant feature.
Key Values
- R1 is 1 k.
- LV1 is 10 mH.
- CV1 ranges from 10 nF to 100 nF.
Suggested Experiments
- Change the position setting and rerun the sweep.
- Adjust R1 to change damping.
- Compare the resonant frequency against the LC estimate.
Featured Component
The variable capacitor tunes the tank capacitance without rewiring the circuit.
Components used
Components used
2 components
SPICE netlist
* ************************************************** * Generated from CircuitSim Schematic ************************************************** C_CV1 N2 0 'max(1f,10n+(100n-10n)*50/100)' L_LV1 N2 0 'LV1_inductance' R_R1 N1 N2 1k V_VIN N1 0 SIN(0 1 1k 0 0 0 ) AC 1 E_VP_TANK VP_TANK 0 N2 0 1 ************************************************** * Models and supporting definitions follow ************************************************** .param LV1_inductance = max(1p,0+(100m-0)*10/100) ************************************************** * Simulation settings ************************************************** .ac dec 30 100 1Meg .save V(VP_TANK) .end
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