Compact Nichia 365nm UV flashlight: Need help on part selection

[jonathandowers]

I'm looking to build a compact UV flashlight with the Nichia NCSU033B LED, and would appreciate advice on selecting parts.

Rough specifications of the light:

• LED: Nichia NCSU033B
• Switch: clicky
• Body size:
  • Ideal: EagleTac A25a clicky
  • Upper limit: Eagletac D25LC2 (head should be as slim as the body)
• Batteries: 1x14500 or 1x18650
• Beam profile: floody. max 120° inclusive, without a hotspot.
• Modes: single mode
• Output: around 3 watts (or whichever current would give the best 365nm peak)
• Usage: Inspection light (currency, and detecting UV reactive items). I don't expect the light to be used more than 10 minutes at a time, with a mean usage time of 15 seconds.

So far I have ordered the LED. Everything else, I need help with (host, driver, optics/reflector/mule, PCB, heatsink, etc).

 

[LilKevin715]

A good host that is similar in size to a D25LC2 would be the EDC 18650 , also available at mtnelectronics sold as a "S3". The NCSU033B has a max current of 700ma with a Vf around 3.8v+ (hard to tell by their datasheet). As for a driver the easy way to go would be a 2 X AMC7135 driver that will provide partial regulation on a freshly charged li-ion (due to the high Vf of the emitter). You could also use 2 X cr123 and it would run in regulation (full 700ma) until the cells would be completely drained.

 

[datiLED]

Have you looked at the Chinese websites for a 14500 or 18650 host? They come complete with everything to build a light except for the driver and LED. You could probably make a workaround to remove the reflector from one of these kits. Use an AMC7135 regulator set to 700mA if you want to keep things on the budget side. Remember to keep the current to the LED at 700mA, or less. That is the maximum for the Nichia NCSU033B LED.

Another option to consider is building an Aleph Mule from parts at the Sandwich Shoppe. They have all of the body parts, but only in bare aluminum. I have this setup in black (with a different tailcap), and it is excellent with a 14500 cell. I love my Mules.

Aleph 1.5X123 (1x17500) Power Pack-Bare Aluminum
http://theledguy.chainreactionweb.com/product_info.php?products_id=1294

Aleph Mule head kit- Bare Aluminum
http://theledguy.chainreactionweb.com/product_info.php?products_id=1127

Aleph Flat Tailcap-Bare Aluminum
http://theledguy.chainreactionweb.com/product_info.php?products_id=841

McClicky2 Switch (Aleph and McClickie pak)
http://theledguy.chainreactionweb.com/product_info.php?products_id=1283

Aleph Cree XR Can

http://theledguy.chainreactionweb.com/product_info.php?products_id=933

GD Buck/Boost Converter Blank (set to 500, or 650mA)
http://theledguy.chainreactionweb.com/product_info.php?cPath=48_49_61&products_id=961

You will need a switch boot and an MCPCB for the LED. If you decide to go this route and can't find a suitable MCPCB, let me know. I have some custom Aleph cans made for the Nichia NCSU033B.

Do some homework, and post back with what you decide. Post pictures when it is done, too.

 

[jonathandowers]

A good host that is similar in size to a D25LC2 would be the EDC 18650 , also available at mtnelectronics sold as a "S3". The NCSU033B has a max current of 700ma with a Vf around 3.8v+ (hard to tell by their datasheet). As for a driver the easy way to go would be a 2 X AMC7135 driver that will provide partial regulation on a freshly charged li-ion (due to the high Vf of the emitter). You could also use 2 X cr123 and it would run in regulation (full 700ma) until the cells would be completely drained.

Thank you so much, I would've found this out the hardway. I asked Nichia, and they've been handwavy about the optimal current.