[moved] Need help! How to check what are the reason to cause inductor burnt?

[sretaw]

Any possible reason that causing the inductor burnt? what are the debug step require to check any of the component is failing? Since visually it does not have any cosmetic problem ( solder bridging etc issue..)see attached circuit diagram and the failure component picture
View attachment Inductor.pdf

 

[KlausST]

Hi,

the only possibility I see: too high current.

Klaus

 

[Relayer]

Hello sretaw,
As KlausST has stated, too much current is passing through the inductor. The enameled copper wire
that constitutes the windings of your inductor are way too thin. Plus due to no resistive load, other
than the inductor itself, what ever +12V rail can supply in regards to current, that's what the enameled
copper wire thickness requires to accommodate it.
You really need to check what current is possible through your circuit.
Try placing a 5W or 10W 100 ohm resistor in place of the inductor, then break the circuit and insert a current
meter and measure the current.
Regards,
Relayer