Low-pass and high-pass filters
The −3 dB cutoff frequency of a first-order RC or RL circuit.
Inputs
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Results
- Cutoff frequency
- 1591.54943 Hz
For RC, output across the capacitor is low-pass and across the resistor high-pass. For RL, output across the resistor is low-pass and across the inductor high-pass. Loading and source impedance are not included.
Formula & guidance
RC: fc=1/(2πRC); RL: fc=R/(2πL)
For RC, output across the capacitor is low-pass and across the resistor high-pass. For RL, output across the resistor is low-pass and across the inductor high-pass. Loading and source impedance are not included.
Change the example inputs and check each field’s units. Use equipment datasheets and applicable project standards for final decisions. Results do not establish Canadian electrical-code compliance or certify a design.