flickering 445nm

[redhook]

ok i'll try look for some ram heat sink. is there a special glue or tape that is a good thermal conductor, but won't do anything towards my electrical things?

This stuff will do the trick.

Newegg.com - Arctic Silver ASTA-7G (2-PC-SET) Premium Silver Thermal Adhesive - Thermal Compound / Grease

 

[jayrob]

it's more like the first. when i power it on it's nice and bright, but then after a while it flickers. if i wait for it to cool and i power it up it's fine, then it starts to flicker again. so yeah i think it's the whole thermal thing from what you guys are telling me.

how would one go about thermally heat sinking a driver? i mean obviously you can't heat sink it with copper or alluminum seeing as it'd connect the circuit. LOL.

glad to know i'm not the only one with this problem

drlava does mention in the V5 documentation that you should put a heatsink on the 5 pin chip for high current...

About the Micro Boost, I have my build set at 1065mA's now. (2 jumpers per documentating, not 3)

It did well with a 1 minute test. Dropped about 20 or 30mW's due to heat, but stable... (still over an Amp after 1 minute - 405-G-1) I don't think the drop in power was the driver. But it was the diode. These diodes seem to be very sensitive to heat...

 

[denton808]

silicone thermal compound?

yeah i saw this as well. does this conduct any electricity?

 

[denton808]

thanks everyone for the info. it helps a lot. plus it's a relief to know that my diode isn't dying XD

 

[jayrob]

P.S. More about the Micro BoostDrive...

The idea of jumping all three pins for up to 1200mA's with a Micro Boost may not be a good idea.

Although drlava says that it can be done, according to this statement of his, he doesn't necessarily recommend it:
http://laserpointerforums.com/f39/i...ivers-portable-lasers-49907-4.html#post737063

 

[Kenom]

I don't think the drop in power was the driver. But it was the diode. These diodes seem to be very sensitive to heat...

I disagree jay. Primarily for the sole purpose of the behavior of the outages. If it was an unstable flicker instead of a almost pulsed operation, I'd tend to agree with you. However he did indicate that it was like the first graph, a consistent really slow pulse that only happened after the driver had been on for a short bit.

Now I'm not saying definitively that I'm for sure right. without having seen this drop in power myself, I can't be sure. I do know the laser I built for BMW with a groove 2 driver and it created the first graph above. It was most assuredly the driver as I pulled the head off and the driver was quite obviously hot. Not warm, but cook eggs hot.

 

[Hemlock_Mike]

I have had the pulsed operation on mine too. Low voltave on the cell, too small cells with not enough current capacity and bad mechanical connections. The micro boost likes to have plenty of current available.

HMike

 

[jayrob]

I disagree jay. Primarily for the sole purpose of the behavior of the outages. If it was an unstable flicker instead of a almost pulsed operation, I'd tend to agree with you. However he did indicate that it was like the first graph, a consistent really slow pulse that only happened after the driver had been on for a short bit.

Now I'm not saying definitively that I'm for sure right. without having seen this drop in power myself, I can't be sure. I do know the laser I built for BMW with a groove 2 driver and it created the first graph above. It was most assuredly the driver as I pulled the head off and the driver was quite obviously hot. Not warm, but cook eggs hot.

I'm not talking about his build Ken...

I'm talking about my Micro Boost build. His flickering problem is most likely due to the V5 driver overheating at that setting...

In my comment, I talked about two different scenarios/two different drivers. So that's where the confusion is. Sorry about that...

 

[nospin]

When I built my 1.5 watt 445 It flickered 15 seconds from the start!
As I described in my post of the build, I guessed driver issue first and shot it with freon
and it stopped, I turned it off, created my pill heat-sink and it NEVER flickered again.

I never suspected anything else, look at the size of the driver!

 

[nospin]

Originally Posted by jayrob: I don't think the drop in power was the driver. But it was the diode. These diodes seem to be very sensitive to heat...

My tests show a similar drop in power due to diode heating

 

[Asherz]

Mine flickered when the batteries ran low on my microboost @ 650mA. Scared the hell outta me, replaced the batteries and it's fine again.

 

[Hemlock_Mike]

I turned my "laser pen" build down to 350 mW because the microboost couldn't get enough from aaa cells for 700 mW :thinking: DUH......
It would flash in 3 seconds.

HMike