Question

In the circuit shown below,
If the switching frequency of the regulator is 25 kHz, then the ripple current of the inductor $\Delta I$ is _______A. (Answer up to 2 decimal places)

Answer 1

Here the given circuit is a Boost regulator,
$V_0=\left(\frac{1}{1-\alpha }\right)V_s$

$15=\left(\frac{1}{1-\alpha }\right)5$

$(1-\alpha )=\frac{5}{15}$

$\alpha =1-\frac{5}{15}=0.6667$

$\Delta I=\frac{V_s\alpha }{fL}$

$\Delta I=\frac{5\times 0.6667}{25\times {10}^3\times 150\times {10}^{-6}}$

$\Delta I=0.89A$