Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Heatsinking a Microboost

Morgan

0
Joined
Feb 5, 2009
Messages
2,174
Points
0
Hi all,

As we know, we are pushing these boost drivers, (I include the Flexdrive here), trying to run 445s at full bore from one 3.7V battery. This creates a lot of heat during the boost and I'm wondering what parts on the Microboost should be particularly cared for?

I have a build in progress and wish to know which side of the Microboost I should be heatsinking for best effect. I did read someone removed the protective silicon blob from the inductor and used that side but I haven't heard the contrary argument. I won't be able to heatsink both sides I don't think.

On the Flexdrive, it seems most of the delicate chips are on the same side so that's not such a problem, although I did notice the inductor getting pretty warm too. Will this happen with the Microboost and does it affect performance with a hot coil?

I'm hoping for some guidance as I'm not the electronics guy I'd like to be so please help a laser brother out.

Many thanks,

M
:)
 
Last edited:





Morgan

0
Joined
Feb 5, 2009
Messages
2,174
Points
0
Thanks for the link TheMonk. It didn't really answer my question though. I know how I'm going to heatsink, I just need know which side to put it on to have the greatest effect. The Flexdrive had both the, 'hot', chips on the same side AFAIK, but there are chips on both sides of the MicroBoost. I have a feeling the inductor may benefit too. It has a large surface area already and bonding that may draw heat away from other components as well. However, I do not know, hence the question.

M
:)
 

jayrob

0
Joined
Sep 21, 2007
Messages
9,862
Points
113
I would take a guess and say maybe the 6 pin chip next to the pot...

But this is a question for drlava...
 

ped

0
Joined
Nov 25, 2008
Messages
4,889
Points
113
I was asking myself the same question morgan, though strictly, Jarob is right, i thought, if im unsure, i'll heatsink both sides...worked a treat.
 

Morgan

0
Joined
Feb 5, 2009
Messages
2,174
Points
0
I did PM Dr.Lava but no reply.

I can't effectively sink both sides ped. I will only be looking for 900mA but it won't be alone.

Experimenting is always the fun bit though I suppose!

M
:)
 
Joined
Dec 29, 2009
Messages
3,136
Points
63
That's about all you can do, then, Morgan. Just figure out which chip gets hotter. Careful, though, might get hotter than you expect. I overfed a green module I have, and it runs like crazy, but one resistor on the driver gets extremely hot. Talking, burned my fingerprints flat in a spot. Also keep in mind that this was the driver to a green laser, nothing as feature-packed and adjustable as the microboost.
 
Last edited:
Joined
Dec 23, 2007
Messages
2,494
Points
0
I actually think its the little square pad by the inductor, that is a FET which is what all of the current goes through (as far as I know)

The little 6 pin chip is the switch, it turns the FET on and off really fast. I don't think any real current goes through the 6 pin one.

The coil is just copper wire around a ferrite core. I don't think heat will damage it...

I've tried asking the same question a bunch of times but never got a straight up answer.
 




Top