I got the emitters from Arrow and reflowed them on Kaidomain’s 20 mm DTP MCPCBs.
I mounted the emitter on CPU heatsink with a nice splash of thermal paste and over the top 16 AWG wires.
I got two emitter types. They only differ in the flux bin with the MF being higer, but I took both to check if there’s a difference in tint. Spoiler: the KF was nicer, but MF has much higher output potential.
Exact order and bin code:
- SPHWHTL3D50GE4RTMF
- SPHWHTL3D50GE4RTKF
Most tests were done with the MF bin, which most people ordered since it was on sale at Arrow.
Purchase links:
https://www.arrow.com/en/products/sphwhtl3d50ge4rtmf/samsung-electronics
https://www.arrow.com/en/products/sphwhtl3d50ge4rtkf/samsung-electronics
In the product code:
SPH=Samsung Package High Power
WH=White
T=Product version
D=Domed lens
5=LH351C (A=LH351D, 3=LH351B)
0=Not defined
G=CRI min. 90 (C=70, E=80)
E4=Forward voltage bin 2.7-3.1 V
RT=CCT 5000 K
MF=Flux bin 250-310 lm, KF=230-290 lm at 700 mA at 85°C
CRI data measured at 700 mA from the hotspot with a
Yajiamei 10° beaded optics (MF bin)
Yajiamei 10° beaded optics (KF bin), nicer tint with less green (duv 0.003 vs. 0.005 on the MF)
Bare emitter (MF) at straight on (0°) for reference
Medium sized smooth reflector from the Eagle Eye X7 (MF)
CRI data with increasing drive current with the Yajiamei optics measured from the hotspot
1000 mA
2000 mA
3000 mA
4000 mA
5000 mA
Output measured in a 50 cm integrating sphere
At 700 mA I measured 306 lumens at 147 lm/W for the MF bin and 290 lumens at 139 lm/W for the KF bin.
The LH351C is rated at a maximum of 2000 mA and 2600 mA pulse current.
The MF bin I tested produced much higher output at high currents than the KF bin.
MF bin
KF bin