Does that graph mean it wouldn’t play well with a FET driver?
Back to the piggybacked 7135 drivers if we want to max the LED?
… or of course an LD-1 / LD-2 from LED4POWER.
Edit: Seems like 4.2volt from a fresh IMR18650 would be way too much power…?
Great info! Pilotdog68 is right, these could be real winners in a 1504. With the larger die I’m not sure there’s much of a throw advantage, but more lumens, similar throw, and longer time in regulation. What’s not to like?
Also, someone above had a good point. The Vf is almost too low. You would have to use a linear driver with this one, no FETs. And it still isn’t as efficient as an XP-G2.
I fail to see the problem. A guppydrv flashed Q.lite and extra 7135’s is cheaper than a good FET driver. Besides the 1504 doesn’t last all that long with a FET driver and XP-G2 anyway. I doubt I’d notice the 10 minutes it loses, not everyone will feel the same way though.
Besides, the die is only about .3mm² larger, so if you can increase the output 13% over the Vf limited XP-G2 you’ve you’ve eliminated the advantage. While it’s not quite there at startup (the XP-G2 will throw slightly further) as the voltage drops the Nichia will overtake the XP-G2 because the Vf is so much lower.
It is more efficient than the XP-G2, the lower Vf makes more than up for the lower output. But in a single li-ion flashlight it runs less efficient initially because the overvoltage of the battery is just burnt up by the driver. Once the battery voltage goes down during drainage, the Nichia runs more efficient than the XP-G2.
The problem is very vain in nature: I like single-sided boards :bigsmile:
I usually prefer linear drivers, but many times I have gone with a fet just for aesthetics. Otherwise, yes, the uber-low Vf is a huge plus. If the high CRI version is as good as this one is, I’ll be replacing a lot of XP-G2’s in my lights.
edit: thanks for the correction Djozz. I see lower lumens at the same amperage and just think “less efficient”. The effect of the lower voltage on efficiency didn’t even register.
Well I looked up n10sivern's test numbers and the XP-G2 S4 2B drew 3.8A in the 1504, I assume that is at start with a full battery. That is 1170 lumen in my graph. The 219C gives off 1170 lumen at 4.7A, it will easily run more current than that so the output will be more than the XP-G2. But the 219C die is about 20% bigger, so it will never throw as well as the XP-G2 with the battery full. But that changes when the battery drains. Actually I did not measure the die size of the 219C, still have to try to dedome it, I just assume it is the same size as the 219B.