Ideambox
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TOOL IDB-ELE-009
RC time constant

Desktop only

Engineering tools are available only on desktop screens.

RC time constant

Time constant, cutoff frequency, and charge times for a series RC. For debounce, anti-alias filters, soft-start, and reset circuits.

Schematic τ = —
Vin R 10 kΩ Vout C 100 nF
Engineering notes

Formulas

  • τ = R · C
  • fc = 1 / (2πRC)
  • Charge: 63.2% in 1τ, 86.5% in 2τ, 95.0% in 3τ, 99.3% in 5τ.

Practical use

  • Switch debounce: target 10–50 ms τ on a Schmitt input.
  • Anti-alias: set fc below half the sample rate.

Result

Live