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ArcticMyst Security by Avery

Micro Boost and LOC 815 diode

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I think what saved you was the batteries must have been somewhat depleted. If you used the microboost to that diode you WERE essentially bypassing the current regulating feature of the driver. Some current loss thru the components sure.

I haven't tried, I know its dangerous, but could you adjust the pot while that diode is connected if so and it adjust then we will have to move on to some others on this that know the driver better than me.

I have some builds laying around that do have case isolated so this is very interesting to me.
 
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gillza

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I think what saved you was the batteries must have been somewhat depleted. If you used the microboost to that diode you WERE essentially bypassing the current regulating feature of the driver. Some current loss thru the components sure.

I haven't tried, I know its dangerous, but could you adjust the pot while that diode is connected if so and it adjust then we will have to move on to some other on this that know the driver better than me.

I have some builds laying around that do have case isolated so this is very interesting to me.

In the name of science :) I will certainly try this during this weekend (most likely later tonight as soon as I am back from work). In the mean time could you explain again in layman terminology why you think that I'm bypassing the driver when connecting microboost to the case (negative) directly? I'm not an electrical engineer but would like to try to understand this :)
 
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I'm far for anything but a student here myself... I believe because the driver is regulating the current using it's components on the - side on the driver. Hence floating neg.

Hopefully a more experienced member could shed some light on this.:)
 

gillza

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I'm far for anything but a student here myself... I believe because the driver is regulating the current using it's components on the - side on the driver. Hence floating neg.

Hopefully a more experienced member could shed some light on this.:)

But wouldn't the same apply to every other diode such as 445 and 405nm ones with isolated cathode and anode pins? The only difference with LOC is that the case itself is used as negative and that little wire from the semiconductor in the diode goes not onto the pin but onto the case?

How about PM'ing the Creator Himself and asking him directly whether Red diodes can be powered by a battery of 3V or less in the setup where module/heatsink with the diode is isolated from the host and microboost is connected directly to the diode?

P.S. I definitely know too little about this to make any concrete statements, just trying to use common sense ;) Thank you for trying to explain this!
 
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good info here--much thanks to all.keep it coming-...LPF is the best!!!!!!
 
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How about waiting for some other electrically gifted member to chime in first... Its best not to cram the good Dr's box up in-between a mass production run of drivers. (flex 5)

Not to be rude. I'm sure he is very busy right now. You might have something we'll just have to wait. Better safe than sorry.
 

gillza

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How about waiting for some other electrically gifted member to chime in first... Its best not to cram the good Dr's box up in-between a mass production run of drivers. (flex 5)

Not to be rude. I'm sure he is very busy right now. You might have something we'll just have to wait. Better safe than sorry.


Sorry :) too late I already PMed him and tried to be as nice and polite as possible. Well I guess it can't hurt. Hopefully some one else will come and explain things.

Thank you for your effort and patience in trying to explain this to me :) I will definitely try what you suggested earlier.
 

DTR

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But wouldn't the same apply to every other diode such as 445 and 405nm ones with isolated cathode and anode pins? The only difference with LOC is that the case itself is used as negative and that little wire from the semiconductor in the diode goes not onto the pin but onto the case?


I have looked into this recently and as I understand it the flex and groove drivers can have the negative from the batter flow into the driver via the driver negative input or output but with the microboost the negative from the battery must come from the battery on a isolated wire to the driver negative input only. And I can tell you from experience that your driver will burn up quick if you don't. Lost a microboost by just shorting the negative and the case pin on a 445 build because there was not a good place to get a ground in the host. The problem was solved by running a third wire from the case pin back to the driver negative input. So this is the number one reason that you cannot use the LOC where the case pin is the negative. To keep the battery negative from flowing into the driver negative output you would need to isolate the host from the heatsink which could be difficult depending on your host.



Here is a link that Jayrob sent me that helped explain this better than I can. Hopes this helps.:beer:
http://laserpointerforums.com/f55/r...-taking-payments-now-48664-21.html#post781362
 
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gillza

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Well there you have it:

drlava said:
gillza said:
DrLava,

I recently purchased one of your microboost drivers and was planning on using it in my LPC-815 setup at 450mA. After reading several reviews and comments I started doubting my decision and decided to ask the creator himself.

Can Microboost be used to drive LPC-815 with the powersouce of 3V or less in the setup where the driver is connected to the diode directly (wire from driver to each pin on the diode) and the heatsink/module is isolated from the host?

Thank you in advance!
Igor

Hi, yes it can. It is a very nonstandard setup but should work. However once the battery drops to 2.5V it will shut off/flash so there isn't much discharge range there.
 

gillza

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Wait he said should work:thinking:

Oh no !... The question has been answered. I ran the diode off of the 3V cr123 battery. It will work as long as you isolate the host. I'll play with the current later and post what I find. The original question was answered by the person who makes the driver :) that is the best answer we will get hehe
 
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at that point, the microboost will be running in direct-drive mode, though, right?

You ought to just put two or three laser diodes in series. Tri-beam ftw!!!
 

gillza

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at that point, the microboost will be running in direct-drive mode, though, right?

You ought to just put two or three laser diodes in series. Tri-beam ftw!!!


It will still regulate, otherwise at 1A of the cr123 battery my diode would have met its maker as soon as I closed the contact... Again I will post current measurements as soon as I am able :)
 

gillza

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Good Evening,

As promised I have tested microboost while connected to the diode. For this purpose I have purchased a new CR123 battery and measured its voltage: 2.95V

Next, connected the driver to the test load to measure its output current: 441mA
20100917232839.jpg


Below is the diode with resistor soldered (I was doing it fast and thus two relatively large blobs are sitting on the pins :) ). Resistor is 1ohm 5W
20100917234343.jpg


Hooked the driver to the diode and measuring current as is with no changes after dummy load:
20100917234652.jpg


Turned the current down:
20100917234754.jpg


Turned up:
20100917235022.jpg


Turned down and up again:
20100917235229.jpg

20100917235443.jpg


Set the driver to 450mA using LD as dummy load :)
20100917235821.jpg


De-soldered the driver and plugged it in into the dummy load without changes:
20100918000415.jpg


Current is regulated :)

P.S. I did not measure the voltage across the diode, I guess I should have...
 
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Hey, I thought everyone was saying this couldn't be done?

I have not gotten to use a micro boost yet.
 
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How about waiting for some other electrically gifted member to chime in first... Its best not to cram the good Dr's box up in-between a mass production run of drivers. (flex 5)

Not to be rude. I'm sure he is very busy right now. You might have something we'll just have to wait. Better safe than sorry.
Not like he has to design them or anything. I'm sure the manufacturer he uses still has all the info...

1. Dial (800) DRIVER1
2. "This is Dr. Lava, I need 500 more flex drives! STAT bitches!"

Bam! It's done!
an important part of selling crap is listening to customers ask the same questions over and over :D
 





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