should i use the forward current encircled with red or the one encircled in blue
Absolute Maximum rating is the max allowed current set by the manufacturer. Above it damage of emitter and/or loss of warranty is very likely.
Unless the heat dissipation is extremely good you shouldn’t go above max rating. For COB this is especially tricky since these emitter type has no thermal pad (a dedicated solder pad underneath which only dissipates heat away from the chips) and is mounted directly to a ceramic substrate.
The Condition only indicates the test current at which the adjacent values are specified. The Absolute Maximum rating is decisive for your project, you should use it (and not exceed it)
so the “sweet spot” would be in between the initial test current (blue circle) and the absolute maximum rating (red circle) ?
It depends on how good is your heat sink. How hot is it when operating for a long time?
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