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445 nM Build review

jbtm

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I already graphed and oscilloscoped my driver to know it ramps the voltage up safe enough to keep my diode happy, thank you very much. As long as you dont hit the driver so a wire lets go, and reconnects, your good. Else your going to have a slight issue with a full discharge to a poor little diode :(
 

Hemlock_Mike

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jbtm -- Here's a little clue I've mentioned many times........

With a CC driver, always add a small -- say 5 ma --- dummy (bleader) load resistor. If something gets disconnected, The regulator won't go to MAX V !!!! I even have dummy loads on my power supplies to prevent the unregulated spike.
Think about it ----
With a CC driver, the resistor won't keep the voltage in range but will discharge the cap when you shut off the input. It's better than nothing.
HMike
 
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Morgan

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This is so interesting I wonder when we might see and, "Advanced Experimentation", section?

We need one, IMHO. I might not understand right now but forming one may change that.

Thanks,

M
:)
 

Hemlock_Mike

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There will be another addition to this thread. WL finally took my order and I have offered a "throw down" to Steve. His 445 vs mine !!! Jay -- I need your best optics!!! Understand that it's easy to crank up the power for a few seconds but I believe here that beam quality will be the issue. Stay tuned......

HMike
 
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JBTM --

Read the info. If you don't understand what I've said, Don't go there - get a driver.
I really hesitated posting info on direct drive here.

I wish there could be a special forum for advanced testing...........

HMike
Well, you inspired me to go direct drive :p
I broke my microboost earlier (busted off a chip while screwing host together :()
It seems to be only about ~100mW or so :undecided:
Definitely not as genius as it was at 750mA earlier :p
But this will hold me over until I get a new driver.
Hopefully it doesn't have too much of an adverse effect on my diode.

EDIT: Also, Hmike, have you measured the current draw on yours?

 
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I have offered a "throw down" to Steve.
Good luck!

Not that you need it, with that monstrosity of a build I'm sure you'll win hands-down :D :D :D

So how did you get the diode and module into the host? Is the inside of the host module-friendly, or did you need a custom heatsink to get the module to fit the body?
 

jayrob

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Well, you inspired me to go direct drive
I broke my microboost earlier (busted off a chip while screwing host together )
It seems to be only about ~100mW or so
Definitely not as genius as it was at 750mA earlier
But this will hold me over until I get a new driver.
Hopefully it doesn't have too much of an adverse effect on my diode.

EDIT: Also, Hmike, have you measured the current draw on yours?

Your running it direct off of an 18650?

If so, what's the battery current draw at full charge?
 
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Your running it direct off of an 18650?

If so, what's the battery current draw at full charge?
Yes, direct off a 18650.
I don't have a multimeter to check, but I'll have access to one in a couple days and I'll see then.
Like I said, the output is low, so I'm assuming the current draw is accordingly low as well.
 

Meatball

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Your cell must have a greater internal resistance than Mike's. What is your cell's rated maximum discharge rate?

EDIT:1000th POST!

-Tyler
 
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Your cell must have a greater internal resistance than Mike's. What is your cell's rated maximum discharge rate?

EDIT:1000th POST!

-Tyler
I don't know, just a cheap trustfire battery, but any li-ion should be capable of 1C or more :p
If my guess of 100-150mW is correct (which I'm basing solely on how much/quickly it burns my skin lol) then the draw should be about 300-350mA.
 

jayrob

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Probably low only because the battery is below 4 volts... (guessing)

I would imagine if the battery was holding 4.2 volts, and it was a quality battery like an AW, it would probably kill the diode!
 
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yahh WL screwed up my order as well said they had no record of purchase.....i was one of the 1st to order but didnt matter to them..when i reordered i had to pay shipping without discount....bs hopefully i will get it this summer....NICE REVIEW H M !!!!!!
 

Hemlock_Mike

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Jayrob ---
I'm betting on the 4.2 volt surface charge on a LiIon cell to be my limiting. Normal cell voltage is 3.7 volts.
This particular diode puts out only 23 mW @ 3.7 V. At 4.0 V, I get about 350 mW and it holds there pretty well. At 4.3 V, I got 1.2 Amps and 1 Watt so I know the diode will take a little more than the 4.2 Surface charge.
When I add the microboost, I will likely set it for about 700 mW.

HMike
 




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