On 29/04/2021 02:07, Paul wrote:
Max Demian wrote:
On 28/04/2021 13:13, Paul wrote:
Max Demian wrote:

(I've seen idiot YouTube videos describing circuits that control
LEDs with potentiometers, either directly or via a power transistor;
it's inefficient and liable to overheat the pot and/or the
transistor as some of the comments say; also I think that
controlling white LEDs in this way is liable to change the colour of
the light.)

Idiot YouTubes:
https://www.youtube.com/watch?v=wns8xrxTYhU
https://www.youtube.com/watch?v=OnjNXhxxc9w


This depends on the situation.

The beauty of design, is keeping an open mind.

It's a matter of whether you like economy and dislike smoke arising
from the circuit.

If you're referring to SMPS problems at low voltage,
an SMPS is supposed to have UVLO. It's not our fault
if a necessary safety feature is missing.

The YouTube videos I linked were ways of controlling the brightness of
LED strips which typically worked on 12VDC. They may have been fed from
a SMPS, but that was irrelevant.

--
Max Demian