How much brighter is a LUXEON K2 over a normal 5mm LED?

[Jbcourt]

How much brighter is a LUXEON K2 over a normal 5mm LED? Is it 2x or 10x? I have been trying to calulate, but cant get it right.

 

[PhotonFanatic]

The brightest of the 5mm LEDs can be around 20-22 lumens, while the K2 can produce 200 lumens, making it 10X the lumen output of the 5mm LEDs.

 

[LukeA]

The brightest of the 5mm LEDs can be around 20-22 lumens, while the K2 can produce 200 lumens, making it 10X the lumen output of the 5mm LEDs.

But over a normal 5mm (not a great one), it's more like 25x.

 

[Illum]

uh...lacking one specified parameter to make the comparison anything near accurate, that's "drive current"

a 5mm LED can "ignite" at half a milliamp, and decay around 150ma, although they can be driven to 200ma but they'll last only for a couple days, if at all.

a luxeon K2 can be driven anywhere from ~50ma to 1000ma...so how much does it more brighter...dunno, it would depend on how your comparing it, from the nominal current the LED is designed for:

25ma for 5mm, 350ma for K2

Or the maximum current each can receive?

~100ma for 5mm, 1000ma for K2

Since the graph relating output and input current is not a even sloping line due to lower lumen/watt efficiency at high currents. I fail to see an ideal point of reference between these two but yeah...a 10-15% increase in output is a pretty conservative estimate.

Usually its best to avoid 5mm LEDs in designing your own lights, whether it's flashlights, LED fixtures, or bikelights when it comes to white light.
Cluster 5mms are

• Inconsistent in gate precision [as in some would light up at different intensities because those LEDs within the batch manufactured may have slightly higher or lower voltages (Vin or Vf)].
• Inconsistencies in tint, or uniform color and usually shifts towards the blue end of the spectrum as they heat up.
• Due to design, they cannot be adequately heatsinked, so expect a shortened function life.
• Hassle to solder in a cluster to [barely] even up to the power of a single K2, Luxeon, Edison, CREE, SSC, etc...
• Since LED drivers are mostly current regulated circuits, its hard to design a light using series connected LED string, paralleling requires a bit of bridging around on a perf board, increasing manufacturing time, decreasing efficiency, and generally tedious

5mms is more than adequate as indicator lights, or any application you can under-drive [or froward a less-than-designed current] it in. a regular non-Nichia T1-3/4 White LED driven at 20ma can last years. However, I've had another LED from the same pack of 10 die in only a day driven around 50ma, and yet another from the same batch that lasted for 3 days driven at 100ma. Assuming 3 hour burn times each day with the majority of the LED legs attached for heatsinking.
Hopefully that gives you a sense of how inconsistent these buggers are.

The same inconsistencies also apply to its bigger brothers, but the magnitude of the impact isn't as significant as 5mms are