Wiring 32 (3-watt) LEDs

Thread Starter

aggx

Joined Feb 20, 2018
2
I am trying to figure out the best way to wire a set of 32 (3-watt) LEDs. I had in mind either doing a parallel set of 16 LEDs or just going with a single string of 32. The LEDs I have in mind are these - VF= 3.2V~3.8V, IF = 700 mA . The LED driver I have in mind is this one - the LPC-100-700 specifically (output = 700 mA, 72~143VDC, 100W). Is this driver sufficient (or too much)? Is there a setup I could use which includes dimming as well? How much heat can I expect to generate and will dimming be of any help or should I consider a using a strobe setup instead (or combination of both)? This project is being setup as a demo 3D project with plastic mock heat sinks. Either way I will be monitoring the temp build up. The final project could include proper heat dissipation if that becomes an issue.
 

WBahn

Joined Mar 31, 2012
29,979
If you want to use a driver than can only deliver 700 mA and you want to drive your LEDs at 700 mA, then you don't have much choice but to put them all in series. Worst case is you need 32 * 3.8 V = 121.6 V, which is within the range of that driver and that would be about 85 W, so you should be okay there, too.

It doesn't appear that this module supports, but I've seen similar modules that do.

It's impossible to guess whether dimming would be of any help or whether a strobe setup should be considered since you give no indication of what is important and acceptable for what you are trying to do.
 

Thread Starter

aggx

Joined Feb 20, 2018
2
Thanks for the quick response, now at least I have more confidence in the direction I am headed in. I had read some folks commenting that these LEDs with their already attached star heat sinks barely got warm to the touch, so it may be fine for demo purposes.
 

ElectricSpidey

Joined Dec 2, 2017
2,758
JFTR, those star "heat sinks" are technically only heat spreaders, I would consider mounting to a heat sink proper for any permanent installation.
 
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