Choose a white LED (and driving method) for flashing brightly

I could use some help finding the brightest LED – or it could be a small array of LEDs – that I can source to flash VERY brightly for a short time (30 minutes or less, mostly just a few seconds at a time) within the following constraints: 9W peak draw of LED circuit, 10-12Hz flashing, min 1000 lumens, available PCB area about 0.35" x 0.95" 0.715" (includes mounting holes). (Said PCB is basically sitting on a piece of anodized aluminum.)

My predecessor on this project did a first-pass bench test of a CREE XLamp MHD-E part (7x7mm, 9/18V, 4000k, 1005 lumen at temp) that may have been acceptable, but brighter is better and I know the first feedback we get is going to be “can it be brighter?” so I want to find out…

Any general guidance – pointers to references, etc. (note that I did give this a read-through: Choosing the correct LED and LED Driver) – would be appreciated!


Thank you for your post.

I was not able to find anything brighter than the MHD-E in the available footprint you mentioned.

One thing to consider is using a reflector/lens combination to focus the light you already have or to increase the light you have without switching leds.

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I’d start the search by paring down things on the basis of the minimum required luminous efficacy–you’re not going to make the target without at least 111lm/w. A person can then select packages that fit into the overall footprint; all else one’s generally going to be better off with a single device, rather than the extra packaging involved when using separate devices. But all else might not be equal… Then one can pare down by nominal flux levels; you’re not likely to get to 1K by 40s, for example… Then ask yourself if you’ve got a bit of wiggle room dimensionally. And of course, ask yourself whether or not available stock is a need…

Offhand, it looks like a person could fit 3 of the JR5050BWT-K-B40EB0000-N0000001 in the stated space quite comfortably, and discounting the quoted efficacy figure a bit, 1500lm could be attainable on your power budget.

As for driving, there’s all sorts of options depending on one’s needs & preferences. The more space constrained and desirous for a plug & play solution one is, the more constrained things tend to be. One can play tricks with smearing “peak” into “average”, such that one’s instantaneous power available on a pulsed basis is rather larger than the average figure, allowing potential for instantaneous brightness to increase in inverse proportion to the desired duty cycle. And of course, thermal management is a thing one has to consider as well.

Some further insight as to your specific needs would be helpful in terms of providing more specific suggestions.

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Some subsequent research confirmed the likelihood of the mentioned J-series device, but also suggested the XPGDWT-01-0000-00ME3 as an alternative approach; their smaller size permits a larger number to be fit into the available space, yielding an array with significantly greater power handling capacity.

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