Decoupling Capacitor Rechner
Berechnen Sie minimum decoupling capacitance to limit voltage droop during transient current spikes.
Minimum Capacitance
50.00 µF
Minimum Capacitance vs Transient Duration
Formel
## Decoupling Capacitor Sizing ### Formula **C = I x dt / dV** Where I is the transient current, dt is the duration of the transient, and dV is the maximum allowed voltage droop. Place decoupling caps as close to the IC power pins as possible.
Lösungsbeispiel
0.5 A transient for 10 us, maximum 100 mV droop.
- 01dt = 10 / 1000000 = 0.00001 s
- 02dV = 100 / 1000 = 0.1 V
- 03C = 0.5 x 0.00001 / 0.1 = 0.00005 F = 50 uF
Häufig Gestellte Fragen
Why use multiple capacitor values?
Different capacitor sizes cover different frequency ranges. Use 100nF for high frequency, 10uF for low frequency, together for broadband decoupling.
Does ESR matter?
Yes. Capacitor ESR limits high-frequency effectiveness. Ceramic caps have much lower ESR than electrolytic.
How close to the IC?
As close as possible. Every millimeter of trace adds inductance that degrades decoupling at high frequencies.
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