On Thu, June 14, 2018 2:40 pm, Dennis Monticelli wrote:
>
> This situation cannot be easily corrected. Trying to add current
> filtering is likely to mess up the feedback loop. Basically, it's a
> redesign. If one goes to the trouble of a redesign then I encouraged
> ripping out the SMPS board and using a linear wall adapter along with a
> series resistor to set the current. Yeah, the efficiency would drop but
> the result would be absolutely zero noise of any kind because the LED's
> themselves are dead quiet.
>
> Dennis AE6C
The problem with this is that the internal resistance of an LED falls
dramatically with temperature, particularly on high output LEDs. You
either have to design worst case, in which case you end up with a fairly
dim LED, or risk thermal run away
The proper way to drive an LED _IS_ with the constant current power
supply, but it does not need to be switch mode.
If you are going to rip out their SMPS, go grab yourself a LM317, and look
at this article for building a higher current supply, and run it in
constant current mode, and that will get you up to 1 amp
See the data sheet or
http://www.bristolwatch.com/ccs/LM317.htm
For more current
http://www.bristolwatch.com/ccs/LM317boost.htm
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