2024-03-14
The Nichia 519A has quickly become one of the most popular LEDs since its initial release in August 2020. Its high CRI paired with a consistently good light color and optical properties make it a good choice for all those who value good light quality.
The 519A has already been used in many flashlights and its optical properties in particular are well known. This test is primarily intended to summarize findings and measured values for this emitter and make them easily accessible. In addition to the 5000 K variant tested here, other 519A variants are also shown without being specifically named, including the 70 CRI variant and the 519BT-V1, which differs only in a few details and has not yet become very widespread.
The 519A tested here comes from a Convoy T3. This was specified with 5000 K and was ordered around the beginning of 2023. Other 519A variants shown here were provided to me by BLF user @thefreeman. Many thanks for this at this point!
Tj 25 °C, If 1,400 mA
- Type: single die, flip chip
- Bin: unknown
- Color group: sm503 (5000 K)
- CRI: typ 90, R9 min 80
- Rated voltage: typ 3.03 V
- Max. Forward current: 2,200 mA
- Max. Peak current: 2,400 mA
- Viewing angle: unknown °
- Thermal resistance: typ 2, max 3.0 K/W
- Max. Temperature Tj: max. 150°C
Datasheet can be downloaded here: Nichia (PDF, 0.8 MB)
The 519A is a simple emitter. The yellow-orange light emitting surface (LES) is surrounded by white silicone with a transparent dome on top. A square marking and some type of code are located in one corner. The 519A-V1 has additional lettering, which is also the only real distinguishing feature.
Handling is easy, the silicone is relatively robust and not very sensitive, although care should always be taken when handling LEDs anyway.
A direct comparison shows that the LES of the 219 family are getting larger and larger, which increases efficiency and maximum achievable luminous flux and potentially reduces the forward voltage. The 319AT with its obscure hexagonal light surface stands out here in particular.
The footprint reveals no surprises. The contact surfaces are gold-plated. The only difference to many other LEDs is the slightly smaller contact surfaces for the anode and cathode. The thermal pad is not reduced in size.
The LES is designed like that of many other flip-chip emitters. A fine granulation runs through the luminous surface. The mixture of these very small blue and yellow dots produces the specified light color. In general, most of flip-chip style LEDs seems to have those granulated surfaces instead of plain and evenly lit ones.
Dedoming is extremely easy to do with the 519A: the dome on the LED can be removed by gently lifting it off with a fingernail. The best results are achieved as long as the LED is warm (e.g. due to previous operation with a higher operating current). This is made possible by a glass-like protective layer on the LED chip, similar to these of the Nichia 719A. No other LEDs with a similar dedoming option are known. The success rate is very high, I am not aware of any failures due to dedoming to date.
The luminous area is 7.2 mm² in size. The flip-chip design means that no bonding wires are visible; the chip is connected from the underside. Light shining through from the side is not visible, which should improve the optical properties.
Within official parameters, as far as known:
- at 2,200 mA (official maximum current): 698 lm @ 3.08 V
- Power at official maximum: 6.78 W
- Efficiency at 2,200 mA: 103 lm/W
- Maximum reached at 7.6 A, at this point 1524 lm @ 3.47 V
- Power at maximum 26.4 W
- Efficiency at maximum 57.7 lm/W
Note: The data given applies to the Nichia 519A sm503 R9080 with dome.
Nichia has set the maximum operating parameters for the 519A very conservatively. The 519A can be overcurrent by four times the specified maximum current.
After dedoming (removal of the silicone dome), the luminous flux drops by around 20 %. However, this is accompanied by a significant increase in luminance, which considerably increases the range in the same optic. This is one of the main reasons why this is done. With the 519A, however, this also serves to adjust the tint; the red tint becomes more intense (the light becomes more ârosyâ).
The 519A and the further development 519A-V1 are not worlds apart. The luminous flux of the 519A-V1 is higher, but this is primarily due to the colder CCT and maybe better flux binning. The thermal resistance is somewhat lower; with a maximum of 8.6 A, the overcurrent capability is somewhat more pronounced. The characteristic curve of the forward voltage is surprising: while it is still lower than that of the 519A up to around 2 A, it rises more sharply and is around 50 mV higher than the tested 519A. Presumably the aim here was to ensure a lower Vf, especially at low operating current (in particular up to the official maximum operating current).
As expected, the 519A with low color rendering (70 CRI) delivers the highest efficiency and luminous flux values. With 2291 lm at 3.50 V, it is in similar regions to XP-G4 or XP-L2 with low CCT, but with significantly higher light quality in combination with optics.
The extremely low dispersion of the Vf is particularly noteworthy despite the different CCT and CRI. It is particularly worth mentioning here that the LEDs tested here were purchased at different times. Either the LEDs come from rolls with very closely spaced production dates, or the production is so mature that consistently high quality can be produced.
A comparison with other LEDs of a similar design shows that more efficient emitters with a similar color space and color rendering are now available. However, it should be noted that 5000 and 5700 K are being compared here; a deviation in efficiency is possible.
The HL2X has no chance. As already described above and in the test, the thermal resistance is too high, as is the Vf. The maximum is reached at just under 6 A. Although it is on a par with the 519A in terms of efficiency up to around 4 A, the light of the HL2X is very green. In this case, part of the efficiency was achieved with a high green tint.
The Samsung LH351D has a higher light flux with its CCT of 5700 K, but its Vf is extremely high. At 4.2 V at maximum operating current, it is higher than that of LEDs with classic bonding wires. This clearly puts the higher luminous flux into perspective. The LatticePower TN3535 corresponds to the LH351D in terms of design and optical properties, but scores points with a lower Vf and similar efficiency. In principle, the TN3535 does everything better than the LH351D, but here too the tint of it is very greenish, which reduces its suitability for flashlights.
Data for 25 °C Tsp (at 85 °C the luminance values are around 13 % lower).
The dedomed 519A offers around 40 % higher luminance than the 519A with dome. Nevertheless, the luminance is low. The 519A is not recommended for use in throwers, and if it is, then only the 70 CRI version, which should achieve a luminance of 110-130 cd/mm² when dedomed. This LED is more suitable for use in all-rounders or floodlights.
There are many lamps with the 519A out there, and also many reviews with beamshots for them. Only two beam shots are shown here as examples. Both are from an Emisar DW4 headlamp with 519A 4500 K, bought in February 2024, one of them with a matt (diffuse) lens. The beam is very good and close to perfection, especially with OP reflectors or diffuse TIR lenses. This is one of the main reasons for the popularity of this LED.
With lenses that are not perfectly calculated, there can be slight tint shift, as is the case with the golden Wurkkos WK03 (TLF Edition 2024) - previously the lens of this lamp was used with an SST-40, and this lens was probably optimized for this LED type and radiation directivity, because with the 519A slight rings and tint shift are visible, although this is not very annoying thanks to the consistently good tint.
There is no tint shift when using diffuse optics. If a lamp with a good light image and also good light quality is required, a 519A should be considered.
Not much needs to be said: the light quality is first class. All 519A tested here have a duv of just under or exactly 0. The color rendering is very high (90 CRI variants). The R9 and R12 are also very high. Due to the slight red tint (sometimes called ârosyâ) in particular, the saturation is higher than in normal daylight. However, this is desired by many users and is one reason for the popularity of the high CRI variants.
The 519A-V1 has a very high CRI of 97 and an R9 of 89, although the R12 is quite low at âonlyâ 77.
It is very likely that there are also âgreenâ variants of the 519A with a duv well above 0; however, these are very rare and hardly exist in the flashlight sector, which is probably mainly due to the procurement of certain CCT binnings by the usual dealers and therefore cannot be generalized for the 519A - in the past there were definitely clearly greenish Nichia 219 LEDs, such as the 219C, which was sometimes measured with a duv above 0.008.
- Ra: 95
- R9: 93
- CCT: 5141 K
- duv: -0.0011
Everyone seems to be talking about the 519A, but I have never tested the LED in my standardized setup so far - until today. Many people prefer this LED, and for good reason.
Good tint, good light quality in optics, acceptable output and efficiency despite 90 CRI. Added to this is the constantly improving availability in various CCTs and compatibility with standard footprints (XP/3535), which makes these LEDs very easy to use in existing lamps. Only certain variants and CRIs are sometimes very difficult to obtain (TLCI, 80 CRI).
Another advantage is the simple dedoming with a very high success rate, which lowers the tint and the duv, which is particularly advantageous for fans of the reddish (ârosyâ) tint and gives more possibilities to create different beams or lighting moods.
Pro
- excellent light quality
- very good beam
- dedoming is very easy
- very good tint
Neutral
- efficiency could be better (90 CRI)
- low luminance (with dome)
Contra
- sometimes difficult to obtain (special CCT/CRI)
Thank you for reading the test. 
scnr