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LED Board

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happypapy

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Hi, Im having trouble with a LED board im making.
It has a total of 10 x 3 watt LED's in a single series, LED's im using are, 1x 20000k, 2x 4500k, 2x 9000-10000, 2x 445, 1x 6500-70000k, 2x 410nm UV.
Some have a lower vF.
The driver im using is a ebay one **broken link removed**
The problem im having is when i light it up, the LED's just flash.
Is this because of the lower vF on some LED's im using?
Should they be moved to the end of the series?

I dont have a great deal of electrical knowledge!
 
You can't drive different LED's in series like that with a single driver, when series driving an LED string you always have to use identical diodes. The numbers you give for the individual diodes don't make sense either, it seems like they're supposed to represent an MCD rating, except the last one which indicates they're a pair of UV diodes with no brightness rating. But none of those values would make sense for 3watt LED's.
 
You can't drive different LED's in series like that with a single driver, when series driving an LED string you always have to use identical diodes.

Why? If the LEDs have the same current rating they can work in series. You should be able to mix RED, GREEN, White and UV. (Series not Parallel.)

The driver will deliver 680mA.
The driver is built to work with a string of LEDs that add up to 36 to 75 volts. If the voltage across all the LEDs is out side that range the driver probably will blink.
 
Because of the power rating...
If the voltage drop is different for each diode even if the current is same the power will be different.

I still want to know what the numbers happypapy listed were in reference to. The coincide with no rational metric I'm aware of.
20k for one, 2x4.5k, 2x9-10k

2x 445, 1x 6500-70000k, 2x 410nm UV

There's nothing reasonable here...
 
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