Rectifier Smoothing Capacitor Calculator
Capacitor value from load current, ripple and frequency.
Smoothing capacitor sizing
After rectification the capacitor charges to the peak and supplies the load between peaks. The required value keeps ripple inside your budget: C = I / (fripple·ΔV), where fripple is 100/120 Hz for full-wave or 50/60 Hz for half-wave.
Example: 500 mA, 0.5 V ripple, full-wave 50 Hz → C = 0.5 / (100·0.5) = 10 mF? No — 0.5 A / (100 Hz · 0.5 V) = 0.01 F = 10000 µF. Use ≥ 1.5× voltage rating and low-ESR types for power supplies.
Values
Result
C ≈ 5000 µF