2024-05-25
Link to original test: Klick
- Bin: unknown
- Color group: unknown (1800 K)
- CRI: 95
Note: There is no official datasheet available!
The emitter was sent free of charge by Fireflylite in mid-May as compensation for a very long delay in delivery. Thanks to Fireflylite for this service!
In contrast to the previously tested FFL351A in 3700 K, the top surface of the 1800 K version is orange. The illuminated area is almost invisible due to the coloring and the thick phosphor. In contrast to most modern flip chip LEDs, the phosphor appears more “segmented”, similar to the surface of stars such as the sun (called granules here), especially at very low operating currents.
As with most modern LEDs and the FFL351A with 3700 K, light is also emitted to the side. Otherwise there are no differences in design and handling to the 3700 K version.
- at 3,000 mA (official maximum current): 560 lm @ 3.22 V
- Power at official maximum: 9.7 W
- Efficiency at 3,000 mA: 57.9 lm/W
- Maximum reached at 9.0 A, at this point 1024 lm @ 3.99 V
- Power at maximum 35.9 W
- Efficiency at maximum 28.5 lm/W
Data for 25 °C Tsp (at 85 °C the luminance values are around 13 % lower).
Due to its very warm CCT combined with high color rendering, the 1800 K version is very inefficient, especially at currents close to the maximum possible. At around 29 lm/W, its efficiency is lower than that of an overdriven halogen incandescent light. The FFL351A 1800 K should not be driven with more than 5 A, particularly because the increase in luminous flux beyond this is only marginal anyway. Nevertheless, the maximum achievable luminous flux of over 1000 lm at 1800 K color temperature is impressive, especially for an LED without silicone dome.
The FFL505A has a considerably smaller illuminated area and a high red component in the spectrum, which is why it is hardly more efficient than the 1800 K version despite its larger footprint. This is a general problem with LEDs with a very small luminous area - the heat dissipation area from the LED chip is simply limited by its surface area and as soon as the maximum heat density for it’s small thermal dissipation area is reached, a further increase in performance is impossible.
The higher Vf and the changed characteristic curve compared to the 3500 K variant are striking. It is possible that a different LED chip is used here, or that the series dispersion is clearly pronounced.
The tint is great and very warm. With 1890 K and a negative duv, the light simply looks good. The high color rendering index makes blue and green colors in particular stand out much better. In comparison, the light of the HL2X 1800 K appears much more orange - more like PC Amber - and blue colors in particular are covered by some kind of “grey haze”, which is also consistent with the lower color rendering index of the HL2X, which is only at around 80.
For all those who are looking for an LED for living room or ambient lighting and prefer very warm CCT, the FFL351A 1800 K is close to absolute perfection. Especially as the beam looks perfect in SMO reflectors, as with the colder version, and there are no annoying artifacts, this emitter is definitely worth another look.
- Ra: 92
- R9: 86
- CCT: 1890 K
- duv: -0.0031
This LED should currently occupy a special position. With XP footprint and therefore maximum compatibility even in existing solutions, quite high output for this warm CCT and high CRI and excellent light in reflectors and lenses alike, this LED is particularly suitable for living room and mood lighting.
Unfortunately, as with many Chinese emitters, there is no information other than that given on the Fireflylite website, and there is also no official data sheet available. Furthermore, this emitter is currently only available in China.
Thank you for reading this short test. 
