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Old 04-30-2008, 05:22 AM #1
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Default 230mW open can in a 2AAA leadlight - stable.

I thought you may like to see this leadlight mod howto that is a proof-of-concept installation of the Micro FlexDrive. Installation of blue ray and red laser diodes into 3V (2 AAA or AA) hosts can be tricky because the diodes require 3.1V at significant current for open can or 5V for the blu-ray. Some solutions have been to use lithium batteries with a higher voltage to overcome the battery voltage sag and driver dropout limitations. However, doing so increases the power that the driver has to dissipate and makes the laser hotter operating and more costly to power.

Here is a mod based on the Micro FlexDrive current regulated driver that is able to drive the diode at 230mW for the entire battery life. The driver is 88% efficient at transferring power to the diode, so little power is lost as heat in the unit.

Steps:

1 - remove existing components except for LED and LED resistor from leadlight driver board
2 - install laser diode in aixiz module and solder leads to the diode
3 - trim edges of the micro FlexDrive so it wil slide in the pen casing
4 - set the driver to desired current
5 - solder driver to diode and leadlight driver board as shown in photo
6 - check spacing and install spacers and insulation around drivers and wires to prevent shorts
7 - install driver and diode stack and batteries with + facing in.
8 - don't look into laser with remaining eye!!
The batteries must be connected with negative to case




balloon pop video (sorry about the angle)
http://www.metacafe.com/watch/1282352/230mw/

Next up: 80mW 2AAA based blu-ray pen laser mod


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Old 04-30-2008, 05:25 AM #2
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Default Re: 230mW open can in a 2AAA leadlight - stable.

see I keep saying awesome driver.
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Old 04-30-2008, 12:57 PM #3
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Wow, a Blu-Ray off of 2 AA's?
I can't wait until I get one
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Old 04-30-2008, 11:16 PM #4
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Default Re: 230mW open can in a 2AAA leadlight - stable.

are you serious? I thought the leadlight was a different case... well, I've got those laying around here, greenies they are... time to take apart!
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Old 05-01-2008, 12:06 AM #5
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Default Re: 230mW open can in a 2AAA leadlight - stable.

WOW! It's like you shot it with a bb gun or something.BAM!Instant destruction!
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Old 05-01-2008, 04:48 AM #6
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Iīm curious abut the schematic of this circuit.
Where I can see it?
tnks.
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Old 05-01-2008, 04:00 PM #7
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Default Re: 230mW open can in a 2AAA leadlight - stable.

if your look closely you can pretty much look up each component from his pictures, and then read their respective PDFs and figure out your own similar working circuit board, it's not as hard as you'd think.
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Old 05-01-2008, 05:06 PM #8
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Yeah I don't think that's likely to happen. *Lava, being the smart person that he is is not going to leave any primary components that are identifyable marked. *So essentially the components you see and numbers you see when searched for on the net aren't going to net you anything. *It's so that his design is not stolen and produced by someone else. *

If your going to take the time to design something as nice as this why would you let someone just come and grab it up and compete with you. *Yes, we are a community of people sharing idea's. *Yes there are drivers out there that will let you do the same thing. *but it's not going to work as well as this. *So as long as you can accomplish driving a laser diode there's no reason to share. *Sell. *that's a different story.

And why shouldn't he be compensated for his hard work? I thinks he should.
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Old 05-01-2008, 05:46 PM #9
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Default Re: 230mW open can in a 2AAA leadlight - stable.

member02: Letīs do it. If you can read as you sad, help-me.

Anyone know whatahell is that component named '101' with 2 and 3 terminal ?
And that other... I canīt read... is lcrb7941 ? is a CI?(Beteween the blue and white wires)

I wanna do this for us, not just for me.

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Old 05-01-2008, 06:05 PM #10
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Awsome laser drlava! im looking forward to seeing how the 80mw bluray goes. =P I really want to try sumthing like this. Is that second board only for the button?


Quote:
Originally Posted by Fred_DASP
member02: Letīs do it. If you can read as you sad, help-me.

Anyone know whatahell is that component named '101' with 2 and 3 terminal ?
And that other... I canīt read... is lcrb7941 ? is a CI?(Beteween the blue and white wires)

I wanna do this for us, not just for me.
what are you actualy trying to do? if you wish Drlava sells thease drivers as kits... maybe that would be easyer for you?
let me remind you this isnt any kind of competition! =P
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Old 05-01-2008, 06:09 PM #11
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Hi Guys, all the labels on the components are there, not marked out. *I reserve the intellectual property rights and copyright on this circuit as it is 100% designed by me, not copied from a datasheet.

If you think that the price for the completed circuit is not economical, once you find what the parts are and what their cost is, you may be surprised to find it is very hard to sell the circuit for less than I am selling it at, and at the same time you would only be stealing the deisign.

You pay over $20 for diodes that often get burned up because of bad drivers or usage, so even in that respect the driver offered through me is not at all a bad deal.

thanks for your interest!

Quote:
Awsome laser drlava! im looking forward to seeing how the 80mw bluray goes. =P I really want to try sumthing like this. Is that second board only for the button?
thanks! Yes the second board is only for the button and light. *Because of the small body size, this laser has a real thermal dissipation issue with the diode getting hot at this power. *The Kryton works much better for high power lasers, so I think the blu-ray pen will end up being a 20mW version instead of a 80mW version.. for diode's safety's sake anyway!
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Old 05-01-2008, 09:37 PM #12
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Default Re: 230mW open can in a 2AAA leadlight - stable.

drlava, I just didnīt know that this drive is yours. Sorry. Iīm not a bad guy whos wanna stole designs registred.
Iīm not in any competition too.
What I want, donīt matter anymore. It was a mistake.

Well... lets forget all this and go forward with your post.

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Old 05-01-2008, 10:04 PM #13
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Quote:
Originally Posted by drlava
If you think that the price for the completed circuit is not economical, once you find what the parts are and what their cost is, you may be surprised to find it is very hard to sell the circuit for less than I am selling it at, and at the same time you would only be stealing the deisign.
I can confirm that is true. I own a company that builds custom designed electronics among other things, and i don't think i could sell something like this at such a low price with any real profit. In fact, i would probably be losing money if i did. $20 is a steal for what it can do.

I don't have this particular driver but i'm using one with very similiar capabilities (but without some of the extras), and i use it wherever i can fit it. I can only recommend this, as it makes previously impossible designs possible. With a 317 you need 3 Li-POs for a Blue Ray, this one can do it from one. It would probably even work from two Ni-MHs if the currents are not too high.


I think it's a great product at a great price! I might even buy some myself, because it's so small and i might not have the time necessary to make the one i'm using right now small enough for some of my laser projects.



Dr_Lava: Is that a coupled SEPIC inductor?
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Old 05-01-2008, 11:08 PM #14
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Default Re: 230mW open can in a 2AAA leadlight - stable.

Quote:
Originally Posted by IgorT

I can confirm that is true....

I think it's a great product at a great price! I might even buy some myself, because it's so small and i might not have the time necessary to make the one i'm using right now small enough for some of my laser projects.

Dr_Lava: Is that a coupled SEPIC inductor?
Thanks for the confirmation, I know with some of the 'enthusiast labor' $4 boards going around it may seem like a lot, but that's an economic reality for what it is.

It is not a SEPIC, I saw those were being tested in the DC/DC thread. SEPIC efficiencies are typically less; this is a synchronous converter.
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Old 05-01-2008, 11:37 PM #15
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Default Re: 230mW open can in a 2AAA leadlight - stable.

And also, if im not mistaking, in the long run these will save you money because they drain the last bit of power from batts and give maximum efficiency Right?
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Old 05-01-2008, 11:40 PM #16
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Default Re: 230mW open can in a 2AAA leadlight - stable.

$20 is like 13 Euro. That's nothing. If it had a couple more components, just the parts would cost as much in small quantities.

What is the "enthusiast labor $4 board" btw?


Oh, and what are the exact dimensions of this thing? Can't find them in your sales thread or here.
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