Selection of components

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3

Selection of components

The inductor and capacitor can be selected using the formulae given below.

3.1

Inductor selection

The minimum value of the inductor can be selected by choosing the maximum of the values

given by the following two formulae:

Iout and Vout are the maximum output current and voltage respectively.

The duty cycles of the PWM signals driving SW1 and SW2 are D1 and D2 respectively.

3.2

Capacitor selection

The minimum of the capacitor value can be selected by using the following formula ,

assuming a variation in Vout of 1% or less

In practice, we take inductor and capacitor values that are larger than the values calculated

using the above formulae.

Lmin =

Lmin =

Cmin =

(1)

(3)

(2)