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% EE3 Boost SMPS Design Report
% Vasil Zlatanov, Sheheryar Salman
% 99 March 2018
# Selection of Components
## Inductor sizing
$$ L = \frac{V_{I} \times (V_{O} - V_{I})}{\Delta I_{L} \times f_{S} \times V_{O}} $$
We require an input current ripple of 10%. At 10V input 20V output and 90% efficiency this would be 0.22A ripple.
$$ L = \frac{ 10V \times (20V - 10V)}{0.22A \times 250kHz \times V_O} \approx 100uH $$
## Maximum Switch Current
To find the switch current we will first calculate the duty cycle required to produce the required output voltage, when we are working of the minimum input.
$$ \delta = 1 - \frac{V_I_M \times \nu}{V_O} = 1 - \frac{8V \times 0.9}{20V} = 0.64 $$
Where $\nu$ is the minimum efficienecy as we want to compensate for power loss.
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