... COB LED package. By now, for small size chip, ?some famous LED chip manufacturer can reach 249lm/watt @ 20mA. But big ... reach 161lm/watt @350mA. The light efficacy decrease when chip size is bigger. Also when LED driver increase current to ... module. COB LEDs have great advantage of thermal resistance, larger cooling area, better lighting effect and high light efficacy. Specification ...