Luminus SST-20-W 6500 K CRI70 color and output test

I got this emitter from Kaidomain on a 20 mm MCPCB.

Mounted on a CPU heatsink with a nice splash of thermal paste and over the top 16 AWG wires.

Purchase link:

Data sheet.

Exact order and bin code: SST-20-WCS-A120-L2651 VK BA

SST-20=self explanatory
W=white LED
C=cool white
S=CRI 70
A=solder pad configuration (3.25 x 3.25 mm)
120=viewing angle, 120°
L2=flux bin rated at 85°C, 530-560 lm at 1500 mA
VK=forward voltage bin, 2.9-3.1 V at 1500 mA at 85°C
BA=tint bin, 6500-7000 K at the BBL

CRI data measured from the hotspot with a Reylight Pineapple OP reflector.

At 500 mA

At 1500 mA

At 3000 mA

At 6000 mA

The tint changes rapidly on lower currents, but after 1500 mA the change isn’t so sudden. My sample seemed to be perfect at about 3000-5000 mA. The tint gets progressively cooler above the peak at currents >7 amps. This was my only sample so I didn’t want to kill it.

Without a reflector straight on the output is very cool and purplish. Also, the tint shift is very strong. This LED has to be used with some sort of reflector or optics. Measured at the rated current of 1500 mA.

Beam tint tested with a variety of reflectors and optics.

Best results with regard to tint shift achieved with a small reflector and a beaded optics, which was to be expected. The larger SMO reflector was not bad at all so it’s very much possible to make a throwy light with the SST-20-W. The 5° clear Yajiamei optics produced the most artifacts/rings.

Output measured in a 50 cm integrating sphere

Thanks for the test. The output performance looks to be very similar to the XGP2 S4 that djozz tested, but with much lower Vf. I think this will be a great option for single-cell triples or quads.

Owe snap……thank you. Tons of great info here. I wasnt around for the “good ole days of the xp-g2’s” but as for lumenss And lux goes, this out performs the current xp-g2 by a good margin.

Thank you maukka

Thank you very much for the detailed review!

I sliced and measured the throw of an SST20 L2 BA 6500K I got from KD. I read people were having problems with solvent dedoming and killing the bond wires, similar to with the SST40, so I went straight for slicing. I have sliced a few SST40s and it’s worked well. The bond wires limit how close to the die you can slice the silicone, so I have been slicing very close to the die over most of the area while leaving the silicone thicker around the bond wires. I used the same method with the SST20, pictured below.

I put the emitter in an EE X6 head to measure the throw at 7m, powered by a constant current power supply.
At 5A I measured 105kcd.
At 4A, 92kcd.
A bit lower than the dedomed XPG2 S4 (new style) that I measured at 115kcd direct drive (probably around 4.5A) with a 30Q. Some of the difference is probably because the dedome is not perfect on the SST20. I think it will be a good choice for multi-emitter lights because of the lower Vf.

Edit: I misremembered the XPG2 throw number. I just measured it at 95kcd at 4.5A. So the SST20 is close in throw.

How does the tint compare with the dedomed XP-G2 S4?

This one was very cool compared to the dedomed XPG2 S4 2B. Like the SST40, the SST20 doesn’t seem to get much warmer upon dedoming. I think I saw some warmer ones on KD, though.

That’s good news thanks, as the dedomed XPG2 S4 2B is way too yellow for me

KD now has 5000K in the high-output 70CRI, along with 3000K and 4000K in the lower output, 90+ CRI variety.

Old thread, I know, but can these be direct driven in a single 18650 light like the c8 with a mid level cell like the 25R? I want to swap into my atrolux C8 with the blf a6 driver, I haven’t done any spring bypasses yet. Would just dropping in an sst-20 (regular cri, higher output version) be usable, or likely to blow the led? is 25r too high output cell? I know if I bypass and use the high output sony cells It’ll probably explode, but how are people using these with the direct drive? Thanks

It depends on a couple of things. How high is the battery internal resistance and what is the current path on the light like.

Assuming a direct connection from battery to the emitter (no host, wire or contact resistance) with a 0.050ohm battery such as the Sanyo NCR18650GA the voltage sag and emitter forward voltage cross at about 6.6 amps which is high but doesn’t necessarily break the emitter yet. Add other resistances and you’re fine. 25R is a lower IR cell and could provide too much current.

Has anyone tried these with any specific Carclo triple optics? I’m curious about the tint shift. I have 10507 and 10511 optics but too afraid to pull the trigger on these. Planning to drive them with an LD-A4 3-6 Amp driver.

Put in SST20’s into my FW3A. I had a 10507 in there and the beam was not smooth at all. The beam had a visible ring in it. So I went with the 10511, which gave a perfectly smooth beam.

What tint did you use and what led was in there before?