I am was assigned a project where I need to design a step-up (boost) converter drom USB 5V to 12V using eDesignSuite.
The only boost converter that suited these criteria that I could find was the ST8R00WPUR synchronous boost regulator.
I have a 1A max USB supply and in theory a max current output of 0,4A calculated from the duty cycle.
I am planning to drive various loads with the curcuit.
I have 2 problems / questions:
The first one is that I am having problem with the inductor selection in eDesignSuite. With a switching frequency of 1,2 MHz internaly in the ST8R00 i would need at least a 48uH inductor to satisfy my need of inductor current ripple of 50mA.
But the selector for the inductor has only inductor selectable up to 10uH, and if I want to add a componet my self it still does not allow a inductor above 10uH. That means that the it goes to DCM already at 0,1A.
Sometimes if I select a low enough current ripple procentage, and then want to add an inductor it says an error of "errors.impossibru".
I would like to know why I cannot select an inductor above 10uH. I have looked through the datashet and part website and found no limitation regarding the inductor, witch is logical.
The second problem I am having is that I found out that you can export your eDesignSuite to a simulation program eDSim created by ST. I thought I could use that program instead to change the inductor.
But currently the ST8R00 has no export to eDSim option like listed in the instructions.
Is there a way to export the ST8R00 to eDsim or any other spice program like LTspice.
I wolud also like to know if there are any other options regarding the boost converter (controler with external MOSFET or regulator with internal MOSFET), preferably synchronous, for my specifications.
Thank you for your help in advance
