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Repair Help: 445nm 1.2w 3-mode micro from wannaburn/JLSE

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This is the actual laser I am attempting to repair:
http://laserpointerforums.com/f39/sold-3-mode-1-2w-s-s-micro-73346.html
I purchased it from 'wannaburn' back in 2012 and it really is/was a fantastic laser.

The Problem: At some point the diode/heat sink assembly became rotationally lose within the host. This allowed the wiring from the diode to the boost board(s) to twist and sever when turning the lens focus ring.

My initial disassembly of the laser for diagnosis (after repeated failed attempts to contact the seller for repair service) was at least a couple of years ago. What started out as a likely simple resoldering procedure has, over the years, become a convoluted crash course in guesswork/reverse engineering and some learned knowledge about laser components and improved soldering skills.

Where I'm at today: twice now I've rebuilt this thing with the same results, i.e., the diode powers on (li-ion cell) and can be cycled through 3 modes, however the output power is minimal at best and the 3rd mode (low/pulsed) flashes on/off like that of a reset digital clock.

I (mostly) assume that the 'mode' chip is working while the boost chip is not. I'd like to determine if I am (hopefully) just missing something in my work or if I've managed to bugger a component on the boost chip. Any helpful advice/consideration is appreciated.
 

diachi

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This is the actual laser I am attempting to repair:
http://laserpointerforums.com/f39/sold-3-mode-1-2w-s-s-micro-73346.html
I purchased it from 'wannaburn' back in 2012 and it really is/was a fantastic laser.

The Problem: At some point the diode/heat sink assembly became rotationally lose within the host. This allowed the wiring from the diode to the boost board(s) to twist and sever when turning the lens focus ring.

My initial disassembly of the laser for diagnosis (after repeated failed attempts to contact the seller for repair service) was at least a couple of years ago. What started out as a likely simple resoldering procedure has, over the years, become a convoluted crash course in guesswork/reverse engineering and some learned knowledge about laser components and improved soldering skills.

Where I'm at today: twice now I've rebuilt this thing with the same results, i.e., the diode powers on (li-ion cell) and can be cycled through 3 modes, however the output power is minimal at best and the 3rd mode (low/pulsed) flashes on/off like that of a reset digital clock.

I (mostly) assume that the 'mode' chip is working while the boost chip is not. I'd like to determine if I am (hopefully) just missing something in my work or if I've managed to bugger a component on the boost chip. Any helpful advice/consideration is appreciated.

How much output power is "minimal at best"?

Have you measured current consumption when set to full power mode? If so, what is it?

Diode could well be an LED, that'd explain the low output power. Test the current draw from the batteries and let us know, that'd narrow it down to the LD well.
 
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paul1598419

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The current on a 1.2 watt laser needs to be more than 10 times 1 mA to 1.2 mA. If it is using a boost driver and you are sure the batteries are not discharged or defective, the driver is most likely bad. That doesn't mean the the laser diode is good, however. Are you certain of your current measurements? Are you sure it isn't 1.2 amps?
 
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My 10% math was a bit "half-baked" at the time :) However, the readings are accurate. The Li-ion cell is at 4.11VDC
 

paul1598419

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Well, if the driver has 4.11 VDC to the input and you are getting ~1 mA to the laser diode, the driver is bad. How are you measuring the current? Are you measuring it at the battery? If so, it's still a bad driver. You mentioned that it has flashlight modes in the OP. Is there a separate driver for the laser diode? I'm trying to figure out which driver is bad.
 




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