Does your LED resistor calculator still hold true for COB and CREE LEds ?

 

CREE is a manufacturer. COB is an arrangement (from Corn COB). If in doubt read the datasheet,

 

No, the forward voltage selector will not go high enough.

 

An old dim 2.1V green LED has almost the same forward voltage as a red or yellow LED.
But a modern very bright green LED has the same 3.6V forward voltage as a blue or white LED.
The forward voltage might be from 3.2V to 3.6V.

 

Does your LED resistor calculator still hold true for COB and CREE LEds ?

It works if you put in the correct forward voltage drop for the LED you are using.
That you get from the LED data sheet.

 

I selected "other " but it would not let me input anything. Has anyone else tried this?

 

COB LEDs have multiple smaller LEDs all in series on a Silicon substrate, and will have a much higher voltage than normal LEDs so it doesn't apply to those.


https://siliconlightworks.com/resoures/what-are-cob-leds

 

COB = Chip On Board. Its like "Baby on board" that we used to read about but this is about mounting semiconductors.

 

Hello,

Bowden has a led calculator that allows you to put in any forward voltage.
http://www.bowdenshobbycircuits.info/led.htm
For the COB and CREE leds, look at the datasheet for the actual forward voltage.

Usualy the COB and CREE leds are driven using a constant current source and not a powersupply with a resistor.

Bertus

 

Thanks for the replies everyone .....