Accurate formula for calculating filter capacitor size on a linear regulator.

[latex]C = \frac{I}{V_R} \times \left(\frac{1}{4f} + \frac{arcsin{\left(\frac{V_{IN}-V_R}{V_{IN}} \right)}}{2\pi f} \right)\\

C=\text{Minimum capacitance required}\\

V_R= \text{Maximum ripple}\\

V_{IN}= \text{Input voltage, excluding diode losses}\\

I=\text{Current drawn by regulator}\\

f= \text{Frequency}\\

[/latex]

[latex]C = \frac{I}{V_R} \times \left(\frac{1}{4f} + \frac{arcsin{\left(\frac{V_{IN}-V_R}{V_{IN}} \right)}}{2\pi f} \right)\\

C=\text{Minimum capacitance required}\\

V_R= \text{Maximum ripple}\\

V_{IN}= \text{Input voltage, excluding diode losses}\\

I=\text{Current drawn by regulator}\\

f= \text{Frequency}\\

[/latex]

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