RC time constant
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Calculate τ (tau) of an RC circuit and get the complete charging and discharging time table. Useful for low pass filters, debounce and PWM→voltage conversion.
τ = R × C
Table 1τ → 5τ
Cutoff frequency
Parameters
Common applications
Low pass filter
R=10kΩ, C=100nF → τ=1ms, fc=1.6kHz. It reduces high-frequency noise in analog signals.
Hardware debounce
R=10kΩ, C=100nF → τ=1ms. The capacitor charges gradually and removes button bounce within a few milliseconds.
ON/OFF delay
R=100kΩ, C=10µF → τ=1s. Combinato con comparatore o trigger di Schmitt: delay preciso senza microcontroller.
See also
Frequently asked questions
What is RC time constant?
τ = R × C. Time to reach 63.2% of final voltage. After 5τ the capacitor is 99% charged.
What is RC cutoff frequency?
fc = 1/(2π×R×C). With R=10kΩ, C=10nF: fc ≈ 1.6 kHz.