Brian Gaff (Sofa 2) wrote:
Its the power supply that often has an issue, depending on what sort it is.
A leaky rectifier for example a capacitor changed in value. They are I think
not built to exacting specs!

Brian


If the LED does not conduct as much current as normal (ohmic),
the "main capacitor" in the SMPS in the light bulb, is
able to pump that tiny current for a number of seconds.

It implies the SMPS is fine, but the LED string has
failed and has managed to add resistance to the path.
This gives the impression the SMPS is giving power for
longer, when it's the LED loading which is less.

Not all bulbs use SMPS. Some use capacitor-dropper
as a technique, for which the symptoms could be
different. Capacitor-dropper bulbs might not
"regulate" the light level, like the SMPS ones do.
Capacitor-dropper bulbs, can be damaged by transients
on mains. SMPS are much more resistant to that issue.

Paul