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FrozenGate by Avery

The SimpleDrive2 - Very easy to set! Now with a feeler!

Johnyz

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Jul 19, 2010
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As I was looking at the drivers we use, I didn't find any budget ones. Aixiz sells some TTL ones, but they have mixed feedback. What comes to mind is our trusty LM317 driver we like to use. Now, the TO220 chip is pretty hard and unreliable to stuff in a real laser host, right? So I made this. *ahem*

The NejTech SimpleDrive2
The circuit we all love, now in a tight package!
Easier to setup than any other driver!

Tested by time!

An LDO chip. A resistive element. A protective diode. A capacitor.
What makes it totally different is the setup method. 5 solder jumpers, just select the diode you have and you are good to go! 445, 12x, 8x, LPC, 6x or PHR?
Just solder the jumper and it's ready to use! No precise turning of the pot. Experimenting with multiple settings
at once is possible, but do so at your own risk. I want to point out that people at National invented it and Daedal reused it for lasers,
I only take credit for the modifications and work in Eagle I done. As said above, this is just a PCB of it adapted to be very small, to fit in a very small host.
I made two models, one using LM1086 in a D2PACK and being able to supply 1.5A. The other one is smaller,
uses LM1117 in a SOT223, supplies 1.2A and will probably be able to fit even in an Aixiz module.

Now for some real-up-close 3D renders using Eagle3D:

D2PACK version:


SOT223 version:


Uploaded with ImageShack.us

Older versions
Any ideas, what to add or change? Feedback is very appreciated!

Want to buy? Tell me in feeler, just click this link!
 
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Re: LM317 - The SimpleDrive - Yes I was bored.

Awesome!:gj:

Maybe you've missed it, but 'jib' made something similar.
Yours has the advantage of being adjustable, his has the advantage of using an IC
with a lower voltage dropout.

So since yours is adjustable without swapping SMD resistors, there might very well be a market for it!
Anyway, great job!

How big is it, would it fit into the back of an Aixiz module?
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Not sure about the larger D2PAK version, but the SOT223 should fit, but I need to get exact measurements to be sure.
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Aww, shoot, and I was just working on this project myself! Wanna check out my design? PM me your email address, maybe we can collaborate.
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Two thoughts:

1) At 1.5A, you're going to need a resistor (or pot) capable of ~2W. Do such things exist? I've never been able to locate a pot that is small and can handle above 1W (if that)

2) I'd use something other than an LM317 for sure. At least an LM1117, but preferably a 1084, 1085 (my suggestion), or 1086. All of these have the benefit of a lower voltage dropout, and the 1084/1085 have the benefit of higher current capabilities (higher than any 445s can handle at present).
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Just a thought, you might consider leaving more copper instead of blank space, spread out the heat path for easier dissipation, to keep the LM cooler.
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Not to hijack, but in my version I used a 1/4W 10Ohm pot and an LM1117 :P
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Right now, I made a quick version with the Vishay T18/Bourns 3006P pot, that has 15 turns and is capable of up to 1.25W. However, unless I find a source of SOT223 LM108* chips, I would have to use LM317 or LM1117 for now. Gonna look how to get the D2PAK to fit there...



EDIT: Done, but certainly, it won't fit in an Aixiz now. Looks like an entire model line could be made.
 
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Merged multiple consecutive posts

@ WOLF... saw you still watching this thread. Where is yours.
NOT a Hijack!

Wolf: looks like the same layout software, and photo hosting.
Is that the "Eagle" Johnyz mentions?

sorry, that was Johnyz post! no wonder it looked the same!
I'm looking for a volume purchase of a drive like this.
 
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Re: LM317 - The SimpleDrive - Yes I was bored.

If I can make a suggestion, why not use the following SMD resistors (available in 2w versions):
0.25, 0.5, 1, 2

Then use solder bridges instead of pots. In reality, you could cover just about every necessary current setting (from 333mA up to 1600mA, with good intervals in between for 405s, and 650s)
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Careful with your thermal pad sizes, pay attention to the datasheet recommendations. The thermals act as the heatsink for SMD regulators since you can not install an external one to their thermal tab.
 
Re: LM317 - The SimpleDrive - Yes I was bored.

RHD: Awesome idea, gonna do something similar in V2 of the driver.

jib77: Yeah, I'm sorting that out, but it's a packed little PCB to work with! Anyway,
you can not install an external one to their thermal tab.
SMT-Kuehlk_2_01.jpg

Are you sure? Anyway, THAT would be difficult to get into Aixiz module. :D

Still, all your ideas are being very helpful to me, many many thanks!
 
Re: LM317 - The SimpleDrive - Yes I was bored.

I love that you're already thinking of a V2 :)
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Thanks, I'm gonna work on it tomorrow (it's 11 pm here).
 
Re: LM317 - The SimpleDrive - Yes I was bored.

Are you going to produce this for real? Or is it just an entertainment pursuit?
 
Re: LM317 - The SimpleDrive - Yes I was bored.

So here is mine...

board.png


Not sure how it compares to his, but mine has adjustable current anywhere from 125mA (for PHR) up to 1.25A or so. Also has an input and output protective cap, a diode for reverse voltage protection, and uses an SMD LM1117.

What do you guys think?
 


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