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FrozenGate by Avery

Driver Design.






@BShanahan14rulz,
Not really, I put OP meaning the "Original Post" then defined it. I'm very interested to see the results.
Benm had concerns that the suggested parts were voltage regulators, not current regulators. I read the data sheets and they are, but are current regulated. This sheds a new light on the compatibility of their use. They may be voltage regulators, but you could pick the desired voltage output knowing they can each provide a max of "**" current preventing a runaway current available situation. The LD will draw the max of each or die trying. Somewhat of a different approach that interests me.
kiyoukan never posted till post #15 if he was following Benm's advice, going on with the 7135's, which ones he ordered or the fact he had other information(posts) to follow.
Sorry if the way I stated it was confusing. I was giving options for the 6v input issue if the AMC7135 was used. There are many ways to control the input voltage.
Normally if advice is asked for, it's followed, or if not the choice and reasoning is explained. I don't see that anywhere so I tried for a clarification in post#14.
"If they are the 7135 or whatever you did get"

I don't think I'm confused at all......................
 
Nope just very helpful.
I plan to do the test today and find out how they work with a test load then put it to a nice red then maybe blue laser.
some of these things are so small.
 
kiyoukan,
Good idea on the test load I was going to suggest it. I would start with just one and measure the current its providing. It is supposed to have thermal shutdown but the test load should indicate its true current output at max load. It would be nice if you have an O-scope to look for any spiking at the regulators output. A 47uF cap on the output should suppress any spiking. They show a 22uF in the L4941 test circuit. LD's are really touchy so a little overkill here wouldn't hurt IMHO.
You also might want to check the heat of the regulator during the test. Since in theory it's going to be maxed, it may require a heat sink to prevent the thermal shut down from activating. It wouldn't be good to have them stacked and individuals dropping out as they reached max temp then kicking back on.
If I'm reading the specs correctly for the L4941, it can go 1A. Do you have a red that can handle that? The LPC-815 can do 500ma max, but thats risky. I have one running @ 453ma. 1A would kill it in the blink of an eye.
Not trying to be critical at all. Just looking for possible pitfalls before it gets to the diode test.

I plan on posting the AMC7135 testing results if they ever get here....lol
I see no reason they couldn't work so far and if for instance 800ma was desired, you could use 3 and regulate one to 100ma. I will find out!

Please post your results!
 
yup. well i was thinking about trying a red but yeah the current is way to high.
So it looks like i get to go straight to risking a blue.
Whoo.
Thats fun.
I wish i had an O-scope but cant afford just maxed out 2 credit cards placing my order hosts and projectors as well as 48 chargers and 48 lenses. blah blah you get the idea.
I do know someone with a broken O-scope. maybe i can fix it maybe not.
 
Edit: parts removed, but offer still stands if you need it.
Anyways, my thought was to drop the Vdd voltage to within operating parameters (Vdd<=6V) using diodes, while keeping the full supply voltage available to the LD (8.4V, in the case of 2 serial Li-Ions). I'm hoping that this way, they could be used with 445nm diodes w/o overheating

If you think it's still going to be a while before they get there, I could send you a 3-up.

BTW, a filter cap is recommended by addmtek if the distance from the 7135 is more than a certain length. http://www.addmtek.com/products/pdf/DD031-AMC7135_D.pdf
 
Last edited:
BShanahan14rulz said:
BenM, you seem to know a lot about drivers. I've been trying to con.. err...convince someone with better measurement devices to try out an AMC7135 with diodes dropping voltage to the Vdd but not dropping voltage to the actual load (as opposed to putting diodes in front of both the load and Vdd, a la cpf user Download http://i127.photobucket.com/albums/p123/StefanFS/3xP7DriverSetupb.jpg).

Do you think this would cause any adverse affects in the current limiting?
Also, a more general question, how clean are these types of current-sink drivers?
Click to expand...

I ordered mine on the 5th , they shipped on the 14th and no update on tracking.
Imagine that.
You asked Benm, I don't want to jump in. I've read many of his posts and I believe he knows that answer. Of course, I'm confused though.
http://laserpointerforums.com/f67/making-your-aixiz-driver-work-solution-56733.html

I read a lot here and referencing, or solving other forums problems is kinda frowned upon. Can't they figure it out? Can't you "con" one of the other forums members? Controlling the input and output isn't that difficult depending on the extent of what you want. The output needs a cap? I think I covered that in post #8. You are not stuck in multiples of 350ma either unless you want to stay in "3 part mode".
You really aren't reading the posts except certain parts so you can prove a point to the ppl on the "other" forum are you?

As far as the parts offer, thanks.....but I'm not in a hurry to solve their problems or prove your point to them.
 
No those I posted aren't LiFePO4, but they make them and if you cross chargers, they burn nice. They even warn you in the ad. Seemed senseless to post every link to a RCR123A out there. The point was an option for 6v input. I find it hard to believe the 900ma ratings myself. Yet postings here have people pulling abt 2C from them at high currents. Never saw much on time duration though. I know some people tested the 10440's rated at 600ma and they barely made 450ma.
 
In addition, with those particular cells, care needs to be taken not to exceed 1 amp current draw or one could easily smoke the diode, rendering them useless ;)

I have links to other RCR123 discharge graphs if you would like to look at them, but not for those cells. Here is some very basic runtime tests with soshine rcr123, but not those diode protected cells.
CandlePowerForums - View Single Post - Some RCR123A Runtimes
 
I can't seem to make you understand that I just pulled those cells as a quick example that a 3v version exists of the RCR123A using 2 for making a 6v input to use with an AMC7135. The OP is doing the build and asked for suggestions. I've lost the protection circuit in Li-Ions and simply removed it to keep the battery in service. Before cutoff is reached(2.75v) it's to low to operate the laser normally anyway. If the 1A diode did fail, it can be replaced with a 2A as they are normally tucked under the isolated "+" button end so they are not actually rendered useless.
2 - 3.7v RCR123A's can be used as easily if 2 - 2A diodes are placed at the 7135's input dropping the 7.4v by 2x1,7v drop for 6v as Benm stated. Yes, I know they will come off the charger higher.....batteries are current rated at the stated voltage. Above that will not have the current to back it up and falls quickly. 12v car batteries are rated in cranking amps @ 12v even though they are charged with a top limit of 13.5v by the regulator. You won't receive that amp rating/capacity on the "surface overcharge". Another possible option mentioned in the thread is a 3A LM350 to regulate the input.
It was stated that it all depends on what the user/builder wants or prefers and the battery issue is now off topic at this point.
In a previous post he elected to go with one of the 3 other controllers he listed so the focus shifted to helping what to watch for using them.
 
Oh I understand what you are saying. In fact, we are saying the same thing, that there is no special reason to use that cell when a silicone diode could be used anywhere in the circuit. Benm said so in the 3rd post, I was just pointing out for the sake of discussion some facts about the battery you suggested in post 5. And 7.
 
Vaporizer said:
Is it that unclear?
Click to expand...
Instead of taking the time to argue with you about that, I would prefer to discuss your comments on the 7135 IC.

Vaporizer said:
I plan on posting the AMC7135 testing results if they ever get here....lol
I see no reason they couldn't work so far and if for instance 800ma was desired, you could use 3 and regulate one to 100ma. I will find out!

Please post your results!
Click to expand...

Vaporizer said:
Alone, your stuck to 350ma or stacked multiples of 350. Might be possible to control or even dump a few ma's on the output to allow them to have those in between outputs one might want.

Edit: The RCR123A can be bought as a 3v not 3.7v. Diodes wouldn't be needed with these. I have 2 of them in transit too.....lol
Click to expand...

What is your theory on how you will be able to dump a few ma or regulate the output of a linear regulator?
 
BShanahan14rulz said:
Edit: parts removed, but offer still stands if you need it.
Anyways, my thought was to drop the Vdd voltage to within operating parameters (Vdd<=6V) using diodes, while keeping the full supply voltage available to the LD (8.4V, in the case of 2 serial Li-Ions). I'm hoping that this way, they could be used with 445nm diodes w/o overheating

If you think it's still going to be a while before they get there, I could send you a 3-up.

BTW, a filter cap is recommended by addmtek if the distance from the 7135 is more than a certain length. http://www.addmtek.com/products/pdf/DD031-AMC7135_D.pdf
Click to expand...

Not sure what kind of mess this post started and not interested in the politics.
As to the electrical part of this what you are saying doesn't make any sense. The 7135 is a linear regulator that must be in series with your load to operate. How is it that you would supply ~6V to the IC but a full 8.4V to the diode? And why would you want to anyhow? The examples you post that download and many others are using for flashlights, don't get hung up on the LEDs, just think of them as ~3.5V diodes. Each one is dropping 3.5V in the circuit, whatever is left over is what the 7135 must burn off, which is just a variable resistor. If you have a supply voltage of 3x4.2=12.6-7V (2xled)=5V leftover (insert laser diode ~4.2V) =.8V as heat. The closer you can get your battery voltage to output voltage the more efficient your circuit will be of course, but also the sooner you will drop out of regualation. Also consider Vin will sag instantly as a load is applied.
 
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