Put a battery in backwards...... :(

Eudaimonium said:

Contact board in it's pill, and solder work on the diode's pins , please.

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Done deal. I am currently at work but as soon as I get home I will take some photos with my dads camera. Now as for the pill, there is thermal tape ( I think its thermal tape.... Its kind of like foam tape) inside there so I will take some before and after photos. The only problem with me removing the thermal tape is that I sont have any to replace it with. Since the laser is basicly toast anyhow I will see about getting some.

Thanks,
jeff

jeffreythe00 said:

Done deal. I am currently at work but as soon as I get home I will take some photos with my dads camera. Now as for the pill, there is thermal tape ( I think its thermal tape.... Its kind of like foam tape) inside there so I will take some before and after photos. The only problem with me removing the thermal tape is that I sont have any to replace it with. Since the laser is basicly toast anyhow I will see about getting some.

Thanks,
jeff

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Oh the laser is far from toast, there is much hope for it. Just not with that driver. New driver will solve the problem.

Thanks in advance for pictures.

Eudaimonium, I have added the photos you requested except there is two problems.

1.) The diode pins are shrink wrapped and I do not have any to put back on. I understand you just want to see if the connections are secure and I assure you they are.

2.) The pill that you speak of is soldered closed. The only way I can open it is if I unsolder it. I do not own a solder gun @ this time and I am in the process of owning one.

If you wish for me to break open the shrink tubing on the diode pins I "can" do so I just prefer not to.

Note: I did not break any of the original connections in the laser and I will not until I have everything I need to fix it.

I have a 6 mp camera that I used for the recent updated photos. I can use it anytime. If you need more photos just ask.

Thanks,
Jeff

You do not actually need a solder tool to remove contact board but I do not want you to remove it, same as heatshrink on diode's pins.

Why they are bended like that I do not know, a bad idea.

Contact board also appears like it was made with epoxy , not a PCB ...

I dunno entire work is a bit of a mess, with exeption of driver, that's a total mess.

Nice copper heatsink though.

Can you try to power this like so, without retuning it into the host ?
Touch + of battery to the contact board , and use a piece of wire to connect negative to the driver pill.

Laser should light up ...

Ehh on second though, maybe better to leave it like this until you get the driver replaced.

Aren't MicroBoost driver coils epoxied on top to prevent them from chipping like this?

drlava has a thread on his microboosts. He says in that thread that they have a protective coating to prevent chipping. I do not know what the coating is made of but yes there is a protective coating. perhaps dave should look at my thread and see what he thinks happend.

Also the 1st picture i posted is a photo before i pulled everything out. I was very careful so that i did not disconnect anything so if you want.... try to load that photo. Btw what do u think about the pictures? Did i do a bad job of taking them? I used a nexus one 5 mp camera and a olympus 6 mp camera.

I believe he said it is just epoxy, to help preventing breaking the ferrite core.

Coherent Light said:

...The Pot has smoked...

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So, which noun is the subject and which is the direct object here... :crackup:

Eudaimonium said:

Hence, battery was hitting nothing more than a contact board secured (pressfited) in the driver pill. Both driver and diode's pins do not suffer any mechanical pressure, which is why I love these Cree lights.

So... back to the drawing board. What could've caused the problem?

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Hmm, that is a good point. Maybe just the damage to the board from being squashed against that heatsink caused some damage that the reverse voltage seemed to just amplify. I still stand by the assertion that it wasn't soldering that was the main cause of this blow-out though.

In this picture, it would appear that the copper "heat sink" was originally "upright" on the inductor. I guess that the builder thought that the inductor is what needed heat sinked. You can see the adhesive pad that would have held it in place. The are probably parts of the inductor's insulation still stuck to it. Also, it is easy to see that the electrical tape is "missing" where this little "heat sink" would have attached

With it sitting upright, the "legs" would be facing the rear of the diode and the copper heat sink from the host. It was probably tall enough to push against the rear of the diode or the heat sink. Screwing the heat sink retaining ring down tight will have pushed the driver heat sink down against the top of the inductor. This is probably what broke the inductor.

Once the top of the inductor broke, the driver heat sink will have moved more deeply into the driver space allowing for the sides of the driver heat sink to contact other components on the driver. This would have produced a direct short between the rear of the diode or the host heat sink and one (or more) of the components on the driver

This short could have found its way "around" the reverse current protection in the driver.



And the builder needs to buy a heat gun

Peace,
dave

Good explanation.

One question, what's a heat gun ? Soldering gun first comes to mind, then hot air soldering station, then DX blowtorch with butane.

Thanks everyone who helped especially drlava. I got a new microboost from him and managed to replace my old busted one. Took about 2 and a half hours but I got it on without any damage and some nice shiny new connections. The diode lived!

So my laser is like new again and I am happy!

Thanks again,
Jeff

Oh and I especially want to thank ed for all the suggestions on equipment. I never soldered before....had trouble getting it to stick but I managed to finally get the nack

Congrats Jeff!

thanks

I'm now working on getting this LOC I got from Greg out of the hs. It will be fun even if I destroy it

Things said:

No SMD diode is going to be able to handle a short from a battery. It most likely failed shorted, sending the full power of the battery into the chip and other components in reverse polarity.

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That doesn't sound right at all. Unless I am just misunderstanding. Do you mean inserting the battery backwards? That is the point of a diode, as long as you don't exceed the breakdown voltage.

Coherent Light said:

The HeatSink was applied to the inductor. IMO it should have been installed onto the Driver IC. It very will could have shorted the inductor to the case.

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CL: certainly agree with you here, but, I don't know the specs of the inductor used in the microboost. Is it possible the inductor is overheating as well, due to series resistance, and perhaps marginal safety factor of the part chosen?

Pontiacg5 said:

The IC is a FET, or field effect transistor. It is what makes the most heat.
(snip)
At that point the diode was probably being direct driven and thats why it was killed when the battery was put in backwards. From the pictures though I can't ever see how the heatsink was on the coil.

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PontiacG5: Yes, you are certainly right about that (the FET making the heat), but would you care to comment as well about what I said above? Do you think there could be any benefit to heatsinking the coil? My electronic theory is a bit weak, so I would appreciate some input from others

The second part, where you mention the diode was probably being direct driven and reverse polarity killing it, can you elaborate on that? These laser diodes, being diodes, can they handle reverse voltage? I did a quick search on laser diode reverse polarity and breakdown voltage but I didn't find the answer I wanted.

Some remarks:
The reverse polarity protection diode can be in series with the battery. In this case a reverse polarity won't do anything. This does cause a voltage drop of the supply voltage, not always wanted. So placing a diode in parallel which is blocking during normal use should also work, if the polarity is wrong this diode will start conducting and keep the applied voltage around 0.6V. But this will short the batteries through this diode, which it probably won't survive.

In my experience a reverse voltage above ~2V kills a diode, or at least damages it enough to die soon.

vegasf6 said:

PontiacG5: Yes, you are certainly right about that (the FET making the heat), but would you care to comment as well about what I said above? Do you think there could be any benefit to heatsinking the coil? My electronic theory is a bit weak, so I would appreciate some input from others

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The coil is nothing but a ferrite core with copper wrapped around it so I don't think that the coil getting hot would effect anything. I don't know too much about inductors, but I don't think I've ever seen an inductor that had it's own heatsink which makes me think it's unnecessary.