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445 nM Build review

jayrob

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I'm using the Micro BoostDrive at 640mA's and it is a very stable dirver...

At this current, I get 530mW's using an AixiZ 405 Glass lens. Or about 610mW's with 405-G-1... (about 15% better)

The forward voltage for my diode at this current is 4.03...

Even though the Micro BoostDrive is a 'boost only' driver. It still works fine. Mose likely the battery voltage sags immediately at that current draw. Which is 812mA's... (full charge)

I did notice that the diode is very temperature sensitive. As soon as the heatsink gets warm from repeated use, the power drops a few mW's. But when you let it cool, it's right back up to where it was...
 
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Hemlock_Mike

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OK JAY --- Your diode is a bit "hotter" than mine. At 640 mA, I would get ~480 mW. Again, it's the luck of the draw on these diodes.
THis is why I repeated my warnings of YMMV !!!! Profile your diode.
Now I hope the innards of my host can handle 1 AMP+ of battery current.

HMike

OH - By the way ----- WL took my order for a Spyder III (but now I have to pay shipping --- again). I told Steve that I would compare mine to his here on LPF!!!! In cooking, we call that a throw down. I have the power advantage since I don't care how long it lasts!!!!
Seriously, Steve has to produce a product which can survive more hours than I care on my build. Divergance will be the real competition.
 
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Benm

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Very nice to see your results Mike!

You are lucky to have it working like this, all the resistances adding up to allow for a direct-drive approach, something only to attempted by experienced builders like yourself.

I really looking forward to the performance with a proper driver though, so you can actually choose how hard you want to drive that diode. I love to see these 445 nm diode experiments, and think i'll be on board myself soon enough.

For me these things fit the bill to build a RGB projector, with true blue getting financially feasible, and by the looks of it, at good power levels too. I just wish they made some 635 diodes of similar power and pricing ;)
 
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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!
I think you're right, and I'm starting to see that this is a bad cell :p lol
Just a moment ago it was very dim so I threw the battery on the charger.
A couple minutes later it was done (what the hell?)
Popped it back in and it was very visible again :undecided:
Definitely got a bad cell here.
 

Hemlock_Mike

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Benm --- I tested this diode with a variable voltage / current supply. When the PS showed 4.2 volts, I knew it wouldn't draw over 900 mA on the cell surface charge and the switches would only add limiting.
The problem now if supplying 1.25+ Amps to a microboost in this housing.

HMike
 

LarryDFW

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Mike;

Here is my "Direct-Drive" 445nm build:



It runs @ 600 ma with a new nickel-anode hi-voltage #18650 2600mah battery @ full charge.

If anybody wants to try "Direct-Drive", make sure you have a good heat-sink to keep the diode cool.

Mine has 2.5 oz. of finned aluminum keeping the laser diode cool.

LarryDFW
445 "Direct-Drive" Member
 
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jayrob

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That's cool looking...

Micro BoostDrive better than direct though...
 

LarryDFW

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Jayrob;

Can't get better efficiency, than a quality host direct-drive.

I am at 100% efficiency @ 600ma versus ~80% for the micro-boost.

As Mike can attest to, high current thru the host connections can limit power.

My run time with a high-capacity quality 18650 will be far longer,
due to the higher efficiency level.

LarryDFW
445 "Direct-Drive" Member
 
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jayrob

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Jayrob;

Can't get better efficiency, than a quality host direct-drive.

I am at 100% efficiency @ 600ma versus ~80% for the micro-boost.

As Mike can attest to, current thru the host connections can limit power.

My run time with a high-capacity quality 18650 will be far longer,
due to the higher efficiency level.

LarryDFW
445 "Direct-Drive" Member

Run time??

There is no way a battery without a driver will keep the diode regulated though...

With a Micro BoostDrive, it will stay in regulation until the battery protection circuit does not let out any more current. In fact, with a quality cell, you can regulate it at 1000mA's.

(I would recommend a protected AW cell for a Micro BoostDrive/445 build)

P.S. I have tried your 18650 cells, and I know they are good quality batteries. I use them in my RPL's... (which have built in protection)
 
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Meatball

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Plus, running them with a driver ensures a set amount of current through the diode throughout the life cycle of the battery. The power through the diode drops off significantly once the battery's voltage drops a tenth of a volt! I vote for drivers.
 

LarryDFW

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The problem is with resistance in the host,
which will drop voltage to the driver,
as the boost driver tries to draw even more current.

Mike had trouble with his host drawing only 300-400ma.

More actual testing is needed to tell the full story.

LarryDFW
445 "Direct-Drive" Member
 
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jayrob

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The problem is with resistance in the host,
which will drop voltage to the driver,
as the driver tries to draw even more current.

Mike had trouble with his host drawing only 300-400ma.

More actual testing is needed to tell the full story.

LarryDFW
445 "Direct-Drive" Member


Not sure what you are talking about??

Are you talking about some problems with a Micro Boost driver?

Just trying to figure out what you mean by that...

I have no problems with the Micro BoostDrive. So I'm not understanding??

One thing I will mention if this is what you are talking about...

The Micro BoostDrive cannot be connected 'battery negative to the driver negative output' like the FlexDrive can.

So if that's what he tried, it will not work that way...

Only 'battery negative to driver negative input'...
 
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Hemlock_Mike

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I connected mine "direct drive" to see how it will work. I am aware that power will drop with voltage but I wanted lower power for divergence testing. The micro boost will be installed after I do divergence testing.

HMike
 

LarryDFW

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Jay;

There is no problem with the "Micro-Boost" driver.

I am talking about resistance in the switch and spring contacts of the host flashlight.

As we demand higher currents for the 445nm diodes, we get higher power losses with many hosts.

Some hosts are better than others.

LarryDFW
445 "Direct-Drive" Member
 
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Hemlock_Mike

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Larry --
I found this again and I think I posted elswhere that the microboost works fine when battery ground is not connected to diode ground. I'm getting 900 mW of 445 with this housing now using a 405 G-1 lens ass'y.
WL seems to have found an order from me (1 OF 2) but no order info yet about delivery. I hope the Spyder III exhibits better beam quality than my build although the 3x expander does wonders.
I plan to do a comparison review in my homebuilt review.

HMike
 




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