A worked example
10 kΩ and 100 µF give τ = 1 s. After 1 s, a 5 V charge reaches about 3.161 V.
RC time constant
Plot ideal charging or discharging and calculate voltage at a chosen time.
YOUR LITTLE WORKBENCH
RC time constant
Start with an example and change it to your setup. Results update as you type.
Calculation method+
τ = RC. Charging V = Vin(1 − e^(−t/τ)); discharging V = Vin e^(−t/τ).
YOUR LIVE RESULT ✦
Time constant τ
1 s- Voltage at selected time
- 3.1606 V
- Five time constants
- 5 s
- Charge fraction at τ
- 63.2121 %
The charging model starts at 0 V, discharging at the entered initial voltage. Ideal components and a constant source are assumed.
| Time (s) | Voltage (V) |
|---|---|
| 0 | 0 |
| 0.5 | 1.9673 |
| 1 | 3.1606 |
| 1.5 | 3.8843 |
| 2 | 4.3233 |
| 2.5 | 4.5896 |
| 3 | 4.7511 |
| 3.5 | 4.849 |
| 4 | 4.9084 |
| 4.5 | 4.9445 |
| 5 | 4.9663 |
THE METHOD / 01
Know what goesinto your result.
τ = RC. Charging V = Vin(1 − e^(−t/τ)); discharging V = Vin e^(−t/τ).
Keep the assumptions clear
The charging model starts at 0 V, discharging at the entered initial voltage. Ideal components and a constant source are assumed.
A FEW USEFUL ANSWERS
Good to know.
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Do I need an account?
No sign-up, paid API or subscription is required. Both language versions use the same calculation logic.
VOLTKIND / TOOLKIT
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