Can you tell me how to figure it out the milliamperes and voltage. I have a Milliampere Meter, a Fluke 16 and a Fluke 87.
Well a bench power supply is the easiest.. Set the current at like 100mA (assuming it isn't a "tiny" led) and raise the voltage from 4v and go up in voltage till it lights. That just gets a general idea of the specs.
Gives you an idea..Pay attention when (voltage wise) the ps goes into cc (constant current ) mode.
Can you post a picture of it?
OR use a constant current driver and a power supply.
Most COB's are like 36V or so. Well depends on architecture. See below.
Soo use an Meanwell LDD 300 or 350hw (Wires make building it easy) and a 48V DC power supply.
Attach the cob to the driver and measure final voltage. Make sure the COB is on a heat sink though.
That will get you the V(f) at the driver ma output.
Now the tricky part is what current the led is designed to take.
I guess in my flippant comment I did overlook that a bit but I was thinking more in usability.
Most of these cheaper cobs should be happy w/ 350mA.
Back to what they look like..
Most run either x in series, y rows. The V(f) of each chip is approx 4V (3.x more likely) for violet chips.
Your voltage will tell you the pattern. Below is 3 in series (4x3 = 12, close to 11)
and 900mA. Since 3 rows you divide so 300mA each row.
Count the little squares inside.
LEDs can "work" over a range of current. Finding how much ios too much without the data sheet is a bit problematic.
Most of the little diodes inside the COB are err "1 watt class"
Very large cobs may use 1/2w or even .2W leds
