# Practical considerations while designing simple boost converter

I understand the step-up DC/DC converter theoretically but there're some questions in my mind about practical design.

Assuming that $V_{in} = 5V$ and I would like to create a variable output voltage. Arduino UNO is controlling the duty cycle $D$. The frequency is 500 Hz.

Is there any practical limitations (restrictions) for the output equation equation: $V_{out} = V_{in} * \frac{1}{1-D}$

If $D = 95$%. Will $V_{out} = 100V$ in real life?

What if I applied a DC signal to the gate ($D = 100$%)? I don't think this will lead to a very high voltage. I think the inductor will just form a short circuit and the load will not receive any voltage. This could damage the inductor as well, Am I right?

What type of inductor should I use? Air cored or axial inductor or anything else?

Is the ohmic resistance of the inductor make a significant effect? Should I put it in consideration?

Selecting a very very large inductor and a capacitor will greatly decrease ripples. But will this lead to any negative effect (side effect)?

Thank you,

• 500 Hz is an awfully low frequency for a boost converter. You'll need a huge inductor. – pericynthion Apr 8 '17 at 17:22
• @pericynthion So what frequency do you suggest? – Michael George Apr 8 '17 at 17:23
• Somewhere in the range of 10 to 50 kHz is probably good for a "learning" DIY boost converter. – pericynthion Apr 8 '17 at 17:34