Thanks for your comment. The IC features an internal current limiting circuit that will take action during the fan startup and will limit the inrush current. So i think that your fan will start-up successfully, even at a lower rate and will reach maximum speed. Also the IC features a soft start circuit that may engage during startup. So i would propose you to give it a try.

I’d like to use this module for running a NIcad 120x38mm fan, but have some concerns about the initial current draw. The fan is rated at 0.27A and 24V, however, I get the sense that it draws much more power than that during the start-up phase (it’s a heavy fan so the blades take a (relatively) significant amount of power to reach maximum speed. As to how much additional current is consumed at that stage, I don’t know, but wouldn’t be surprised if it reached something like 2.5-3A. Is there a simple way of modifying this module to withstand this level of current (I don’t mind paying for more robust parts etc.). Your advice on this would be much appreciated!

Hi Thomas, I reviewed the simulation on my end and a 150uH/4.3A inductor has been proposed as ideal. I don’t know why this is different from your results. Probably both solutions works quite well. I also checked the inductor current on steady state operation and it has a max current of 2.35A, so probably there is some room to use a lower value inductor.