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

PREVIEW: "Pico" - A really tiny 2.4A+ buck driver.

rhd

rhd

0
Joined
Dec 7, 2010
Messages
8,475
Points
0
Just a preview. I haven't decided what the future of this guy is (if any). It's so painful to reflow the IC (not pictured) that I can't imagine it ever being a useful driver for anyone else - it's more of a curiosity.

6.35 x 6.35 mm, which is 41 square mm (for comparison, the FlexDrive is 108 square mm). That's the smallest board that Oshpark can create - though the version on the photo was actually fab'd by iTead, because I wanted the cool red color.

I don't have much more to say about this guy until I've experimented a bit more, which could be a while. But as a starting point, it does 2.4A just fine, and I think it may do 3.7A for the new 3W diodes. I'll report back on this in the future.

attachment.php


attachment.php


attachment.php
 

Attachments

  • IMG_20140602_215944.jpg
    IMG_20140602_215944.jpg
    93.8 KB · Views: 480
  • IMG_20140602_220344.jpg
    IMG_20140602_220344.jpg
    86.9 KB · Views: 505
  • IMG_20140602_224403.jpg
    IMG_20140602_224403.jpg
    116 KB · Views: 506
Last edited:





sinner

sinner

0
Joined
Oct 27, 2011
Messages
2,565
Points
83
Another awesome driver. Your expertise are very useful for the forum. +rep If I can.

Please do make some arrangements with some veteran member(s) or yourself to make them available for the masses , and the boost driver too. I can think of many people that could simply start building lasers again if these drivers become more common.
 
dubious speculation

dubious speculation

0
Joined
May 12, 2013
Messages
751
Points
43
Wow! another awesome driver from Rhd :D

It is hard to believe that this driver has a much smaller footprint compared to a flexdrive. I can see these being widely
used by many members if they where readily available. It would open up a whole new realm of small applications.

Your expertise and contribution to the forum deserves everyone's praise, +1 :beer:
 
crazyspaz

crazyspaz

0
Joined
Jul 4, 2012
Messages
2,834
Points
63
Wow, ANOTHER tiny, useful, and (correct me if im wrong) cheap driver. Will this be open source as well?
Also, why is soldering the IC so hard? Because its so tiny?
 
sinner

sinner

0
Joined
Oct 27, 2011
Messages
2,565
Points
83
Why all the good things in life have to be TQFN or BGA!

:scared:
 
IsaacT

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
ARG said:
Must be a TQFN or BGA :p
Click to expand...

What is a TQFN or a BGA?

My guesses:
The Quilt Feels Nice
Big, Glorious Ass

In response to the OP: this is fantastic, but would show my soldering skills for what they are, an awful blundering about with some luck lol.
 
Sigurthr

Sigurthr

0
Joined
Dec 11, 2011
Messages
4,364
Points
83
Very interesting! I'm curious what the dropout voltage and thermal aspects are. My money is on BGA.. TQFN's can still be bodged somewhat easily if you are determined.
 
rhd

rhd

0
Joined
Dec 7, 2010
Messages
8,475
Points
0
Here's an approach for even tighter builds:

attachment.php


On-diode 2.4A buck driver for 9mm diodes.
Just under 12mm diameter.
Two or three cell input.
 

Attachments

  • on diode buck.png
    on diode buck.png
    363.5 KB · Views: 317
Last edited:
andrewb

andrewb

0
Joined
Sep 7, 2011
Messages
144
Points
28
Amazing work.

So if you don't mind me asking, what's the magic sauce?

(i.e., what is the advancement that is allowing such smaller layouts compared to existing drivers?) Are you disclosing what part you are using? (Ok if not.)
 
crazyspaz

crazyspaz

0
Joined
Jul 4, 2012
Messages
2,834
Points
63
Awesome. 2 questions though:
1) what happened to the big inductor?
2)if you use this on the back of, say, a 5W NDB7A75 build, wont a significant amount of heat from the diode transfer to the driver? So really, what kind of overheating issues could/would you run into?
 
rhd

rhd

0
Joined
Dec 7, 2010
Messages
8,475
Points
0
crazyspaz said:
Awesome. 2 questions though:
1) what happened to the big inductor?
2)if you use this on the back of, say, a 5W NDB7A75 build, wont a significant amount of heat from the diode transfer to the driver? So really, what kind of overheating issues could/would you run into?
Click to expand...

The big inductor is a small inductor this time around.

This particular driver is pushing some of the limits of smart design (intentionally - but it's pushing the limits nonetheless). Most notably, I'm using a bit lower inductance than I'd be comfortable with normally.

It was more a proof of concept than anything else.
 
You must log in or register to reply here.




Top