I was testing a SMPS (boost) where I had an overcurrent due to overload for a few seconds.
The inductor saturation current is 2A.
Although I could not measure the current, I am quite sure that the current was a few times higher than the saturation current.
I was able to switch off everything within a few seconds.
After that I removed the load and the converter works fine under no load.
However, when I connected a load which was previously working fine, the converter is not able to deliver the current and goes crazy.
Basically same behaviour as in the "failure/overcurrent" case.
I checked and inspected all the components, they look fine.
So based on this my hypothesis would be that the short "failure/overcurrent" has changed the inductor characteristics. In particular the saturation current has lowered.
I could not find any information online whether this is physically possible. Is there anyone who can shed some light on this?
(I am using a shielded SMD box inductor.)
BTW: Unfortunately, I don't have an LCR meter to measure the inductance.