short answer:
I think it is common for there to be visible flicker, if I look very closely, in all the 2019 and 2020 drivers.
long answer:
I tried to eliminate the flicker in one of my lights that had a 2020 driver, by trying different LEDs. It made no difference
stock XM-L, sw45k, sw30, 519a 4500K, they all flickered w a 2020 driver
I swapped in a 2019 driver… it made no difference, still flickered
I asked a couple of modder friends about their RRT-01 lights. the ones w 2019 and 2020 drivers… all flicker. The combined total of lights that flicker is about a dozen.
our drivers that do not flicker are from 2011 and 2012, a sample of about 5 lights.
I have not seen this documented anywhere, these are just my own personal observations and those of a couple people I know.
some driver feture change history:
1. the original 2011 driver has no strobe. Initially rated 500 lumens, later models 600 lumens. I believe the output increase was due solely to a change in LED model.
2. the 2012 driver adds strobe, it was used in some RRT-01, also in the NiteEye Eye10, and in the Jetbeam TCR-1 (the titanium RRT-01). These were still claimed 600 lumen on packaging. (and I find that is ballpark accurate on my homebrew meter)
3. The 2019 driver output claim writen on the packaging is 950 lumens (they tend to test a bit lower). I believe the increase is due to a component change in the driver. 2019 drivers also have strobe, like the 2012 driver. The 2019 host is a redesign, with a heavy brass pill, but the drivers are still the same size and interchangeable w 2011 and 2012 drivers.
4. The 2020 driver adds a tailswitch (no tailswitch on the earlier models), and a thermal step down component to the driver (still claimed 950 lumens on the package, like the 2019 driver, and still has strobe like 2012). The 2020 host is a redesign, the control ring gets a lubrication hole so no disassembly is required. The drivers are still the same size and interchageable with earlier models.
we can still buy 2019 and 2020 drivers, but not the 2011 nor 2012 drivers
in this pic left to right Niteye Eye10, 2011 RRT-01, TCR-1, Niteye Eye10
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in this pic is the Niteye Eye10 TiC on left, the Ti version of the Niteye Eye10:
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the Niteye models have fins on the head, in the case of the Eye10 TiC, they are factory drilled and tritted
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l-r Sunwayman V10r Ti, Niteye Eye10 TiC, Jetbeam TCR-1, Russtang EX10 Ti:
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fwiw, the Sunwayman V10r Ti, on left, does not flicker, nor do the aluminium version, the V11r.
Sunwayman drivers are different than the Jetbeam/Niteye drivers, not interchangeable. The Sunwaymans use a tailswitch.
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