This tool calculates the cap value (Farad) for a power supply. The power supply is either a full-wave or half-wave rectifier.

**Calculator**

Enter

- Type of power supply
- Desired ripple voltage (ΔV),
- Load current (I)
- Frequency of the power supply (f)

**Example Calculation**

For a full-wave rectifier, with a load current of 2 Amp, 60 Hz frequency and Ripple Voltage of 1 Volt the required capacitor is 16.7 mF. For a half-wave rectifier with the same input parameters, a 33.3 mF cap is required.

Note the larger the value of the cap, the larger the RC time constant. This is consistent with the fact that with a half wave rectifier, the settling (or discharge) time is longer.

**Formula**

**C = I _{LOAD}/(2*f*V_{Ripple})** for a full wave rectifier

**C = I _{LOAD}/(f*V_{Ripple})** for a half wave rectifier

where,

**I**is the load current_{LOAD}**f**is the frequency**V**is the peak-to-peak voltage ripple (calculator)_{Ripple}