I'm making a buck regulator using L4970A using circuit from this application note figure 60 , except for the inductor. I change i to 180 uH
I wanna make it to be a power adaptor for laptop with solar cell source (about 100 W, Voc 27 V, Isc 5A), and the regulator itself can hold current to 10 A max, said the datasheet
As you know, usually laptop needs current from about 1.5 A-4 A, depends on it's using battery or not and how the laptop works. I've succeeded to make my regulator give supply to the laptop, but the current is too small to make it becoming primary supply.
Does anyone know what's wrong with the design? What actually limits the current of buck regulator??
I test this circuit using Asus A43SJ
For Russel, this is my inductor
I don't know either the wire type or the core type exactly, but because it's not magnetic, I think it's iron powder. Outer diameter 2.3 cm and inner diameter 1.2 cm