268mW 6X Key Chain Blu-ray! (With FlexDrive!) - Awesome!

[jayrob]

Re: Key Chain Blu-ray... With FlexDrive!

In theory, putting a silicon diode before the FlexDrive would protect the battery from dropping below about 3 volts, because the FlexDrive needs 2.5 volts to operate.

Now fitting a silicon diode might be a little tricky, but it could be done. There is some room between the LD and the button/driver sandwich.

Hmmm... I may take mine apart and fit them with silicon diodes for extra battery safety.
Jay

 

[suiraM]

Re: Key Chain Blu-ray... With FlexDrive!

heh... ya, tell me about it - I have these little LiPo's about 1cm square x 1mm thick...
10mAh looking for a purpose in LiFe

Where did you find them?

I would positively love a handful of those.

 

[DayOfShadows]

Re: Key Chain Blu-ray... With FlexDrive!

Well i got a 10180 laying around im not useing and i have the matching charger i wonder what i should do with it =?
Edit: just found my other one so i have 2   too bad my tiny laser is dead  :-/  :'(

 

[IgorT]

Re: Key Chain Blu-ray... With FlexDrive!

In theory, putting a silicon diode before the FlexDrive would protect the battery from dropping below about 3 volts, because the FlexDrive needs 2.5 volts to operate.

Now fitting a silicon diode might be a little tricky, but it could be done. There is some room between the LD and the button/driver sandwich.

Hmmm... I may take mine apart and fit them with silicon diodes for extra battery safety.
Jay

Yeah, but it would also reduce the efficiency quite a bit..
Only with a linear driver can a diode be added withot reducing the efficiency.


Less efficiency means more  heat (dissipated by the diode) and shorter battery life (even worse). Si diode would also drop 0.7V which is too much.
If anything it should be a Schottky. They have a Vf closer to 0.35V => 2.4 + 0.35 = 2.75V = Li-Ion minimum discharge voltage = perfect match (still reduced efficiency, but MUCH less - i should calculate it...).

Also, schottkys can be had REAL tiny! Look at the diode on the input cap of my boost driver, in your AAA host. That's a Schottky. That wouldn't be a problem to fit in there.


But i think, that on small batteries like this, the FlexDrive would start blinking faster than on big ones, which can still provide some juice, even after they shouldn't... Does it start blinking, when the battery goes low, or does it just shut down?

Turn it off when it blinks, and measure the battery voltage asap. I'm guessing it'll be over 2.7V (of course under load it was less).

 

[danq]

Re: Key Chain Blu-ray... With FlexDrive!

Where did you find them?
I would positively love a handful of those.

Powerstream
there are a number of sizes of these ultra-lights; a lot of possibilities, but probably won't be too useful for lasers.

But that little 10mAh unit will power an efficient led for a loooong time! I had one hooked up to a little blue LED that took only 100uA to get bright - yes, thats 0.1 mA - I didn't get 100 hours out of it, because I had to clear my workbench so disconnected it at about 3 days. Cool though!

The last time I ordered from them I picked up one that's 1mm x 44mm x 61mm, 200 mAh! they are supposed to be bendable...
 ;-)
DanQ

[highlight]EDIT[/highlight] oops! when I bought mine, a while back, they had some really cheap, defective or something... now they're $20 each!

 

[Kenom]

Re: Key Chain Blu-ray... With FlexDrive!

those batteries are absolutely AMAZING!

 

[jayrob]

Re: Key Chain Blu-ray... With FlexDrive!

Igor, how about a 3.0 volt Lithium primary battery?

Here is an option to also use a Lithium primary battery with 160mAh capacity!

This should work...

The I.D. of this host is just over 12mm. A 3.0 volt CR1/3N Lithium primary battery is 11.3mm diameter X 10.8mm long. I have some little magnets that are about 9 or 10mm in diameter and over 3mm thick each. So 2 of the magnets will fit this host perfectly with the CR1/3N primary.

These batteries can be had for about $2 bucks a piece on-line. They have a much higher capacity than the 10180, even though shorter in length. The capacity is 160mAh. Some brands say 170mAh.

More capacity, with no over discharge worries!

Here's a picture of the 'thick' magnets with a 10180. The host is brass, so no problem with the magnets...

Jay

Update: Scratch the idea of using the CR1 batteries. It works, but not with full power. I got 75mW's with the red build. 128mW's using a 10180.

 

[IgorT]

Re: Key Chain Blu-ray... With FlexDrive!

Sure, if it has 170mAh!

I'm looking at the Conrad catalog for more Li-Ion shape and sizes...


EDIT: No luck with Li-Ions, but i did find 12mm dia / 6mm height Ni-MHs! Three of these would fit, and work, but the capacity is 40mAh.. We're better off with 10180's...

I also found a 3V Primary Lithium, 11.6mm dia / 10.8mm length, from Varta.. Capacity says 170mAh!
I think this is the same you found. CR 1/3N... If only it was a bit longer and more capacity.. In Conrad it costs 5.3€!

Problem with Lithium Primaries is, the FlexDrive won't really use them up fully, since it'll stop at 2.4V. It's possible only half of this capacity would be utilised (since primaries should go down to 2V), maybe a bit more than half, but then you're pretty much back at where you were with the 10180...


I will be happy if i can get those. Li-Ions have the highest energy density, and are in the perfect voltage range for boost drivers.
Unless the tailcap can be drilled out (without reducing the integrity of the threads) to make room for a longer Li-Ion, i think 10180's are the way to go for a project like this.

It's amazing, that it's possible at all! The 10180 will actually power a 200mW red or a 6x, even if it's only for a short time. But that's why they are rechargeable. 200mW in this size is beyond anything i ever imagined..

The only thing better would be a 12180 Li-Ion - it would have twice the capacity! Oh well, i can dream..

 

[Dr.LaSeR]

Re: Key Chain Blu-ray... With FlexDrive!

look at this charger on DX !
http://www.dealextreme.com/details.dx/sku.11968
for $2.94

like the one you are using but powered by USB

 

[IgorT]

Re: Key Chain Blu-ray... With FlexDrive!

look at this charger on DX !
http://www.dealextreme.com/details.dx/sku.11968
for $2.94

like the one you are using but powered by USB

Oh crap... I already bought two of those "expensive" ones....  :-[


EDIT: Wait, that's not a coin CELL charger, that's a universal CELL phone battery charger! Don't buy that for coin cell's or tiny Li-Ions! It'll fry them!

It's not the same thing, even if it looks slightly similar. This is for BIG batteries, the other one is for small one, and has a really low charging current. Definitelly not 250mA!

 

[jayrob]

Re: Key Chain Blu-ray... With FlexDrive!

It's amazing, that it's possible at all! The 10180 will actually power a 200mW red or a 6x, even if it's only for a short time. But that's why they are rechargeable. 200mW in this size is beyond anything i ever imagined..

The only thing better would be a 12180 Li-Ion - it would have twice the capacity! Oh well, i can dream..

I have my red one set at 180mA's just because I want at least 1/2 an hour of run time. But using a 1239JL-54 diode, with an AR coated acrylic lens (thanks for that e-bay link Igor), I get 128mW's! Lights matches easily at my standard 5' burn test...

But for a hand picked high efficiency 6X diode. 180mA's would put you easily over 200mW's of blu-ray! Especially when we get your 405nm glass lenses for AixiZ.

I found one really high efficiency 6X diode that gives an incredible 220mW's at 192mA's through an AixiZ acrylic! This particular diode, set at 180mA's, would still be over 200mW's, even through an AixiZ acrylic lens!

To take the pressure off Igor, this is not a 'normal' 6X diode, and I would imagine, would most likely not be something you could expect to get from a builder...
Jay

 

[IgorT]

Re: Key Chain Blu-ray... With FlexDrive!

Wait, you found those lenses afterall? Are they available again?
I thought they were all out! They are very decent not too expensive 660nm lenses, are they not?

I wanted to send you one, but realized i was all out. I'm very glad to hear they have more! (if i understood correctly)


About the efficiency, i read you selected a special high efficiency PHR for the tiny build. That was a very good idea! Same would work miracles with a tiny (or should i say "micro") 6x build -  you get longer battery life, less heat AND more power all at the same time!

Altho there are sometimes freak 660nm diodes too, you know..
I made an open can Dorcy for Scopeguy (as thanks for all his help), and that diode did 295mW after the AR acrylics at only 430mA!


Also, consider this: 405nm diodes, while they do need less current for the same power as reds, require more voltage for that current to flow! Because of that, the power going in for 200mW of blu to come out, is not much different than the power going into a 660nm diode for 200mW to come out on the other side..

And since you are using a swithing driver here, it doesn't matter how much current the diode takes, what matters is how much power it takes!


- Let's say you power a high efficiency 6x at 180mA to get 200mW.. The power going in will be Pin = 0.18A x 5.2V =  0.936W...
- Now take a good 16x diode, and also set it to 200mW, it takes some 300mA to do so. Pin = 0.3 x 3V = 0.9W <-- it's actually less power than the 6x needs for the same optical power to come out!

In the first calculation i used actual PIV data, for the second, i made a guess, but you see my point.
If the efficiency of the red is the same as the efficiency of the blu (not mW per mA, but mWo per mWe - actual efficiency - the ratio of optical power OUT to electrical power IN), a switching driver will draw the SAME amount of current from the battery to reach the same power with both!

Now switching drivers sometimes have a slightly higher efficiency at higher output voltages, so the losses in the driver with a red will be a tiny bit higher. But if you use the 660nm AR coated acrylics, i see no reason not to get the same battery life with a 200mW red as with a 200mW blu..



EDIT: (Did i miss this, or did you add it?)

I found one really high efficiency 6X diode that gives an incredible 220mW's at 192mA's through an AixiZ acrylic! This particular diode, set at 180mA's, would still be over 200mW's, even through an AixiZ acrylic lens!

That's a total freak, man!
You could not possibly find a better diode for a micro build!

I hope i find one like that! Did you by any chance plot it?

There is only one concern here. I noticed with some "high efficiency" 4x's, which put out way more power at the same current than others, that they took a higher voltage for that current!

So while mW per mA was higher, and made it seem high efficiency, mWo per mWe was not necessarily higher. And it is that, that matters in a case like this. That's why i'd love to see a PIV plot of this freak 6x.

 

[jayrob]

Re: Key Chain Blu-ray... With FlexDrive!

Wait, you found those lenses afterall? Are they available again?
I thought they were all out! They are very decent not too expensive 660nm lenses, are they not?

I wanted to send you one, but realized i was all out. I'm very glad to hear they have more! (if i understood correctly)


About the efficiency, i read you selected a special high efficiency PHR for the tiny build. That was a very good idea! Same would work miracles with a tiny (or should i say "micro") 6x build -  you get longer battery life, less heat AND more power all at the same time!

Altho there are sometimes freak 660nm diodes too, you know..
I made an open can Dorcy for Scopeguy (as thanks for all his help), and that diode did 295mW after the AR acrylics at only 430mA!


Also, consider this: 405nm diodes, while they do need less current for the same power as reds, require more voltage for that current to flow! Because of that, the power going in for 200mW of blu to come out, is not much different than the power going into a 660nm diode for 200mW to come out on the other side..

And since you are using a swithing driver here, it doesn't matter how much current the diode takes, what matters is how much power it takes!


- Let's say you power a high efficiency 6x at 180mA to get 200mW.. The power going in will be Pin = 0.18A x 5.2V =  0.936W...
- Now take a good 16x diode, and also set it to 200mW, it takes some 300mA to do so. Pin = 0.3 x 3V = 0.9W <-- it's actually less power than the 6x needs for the same optical power to come out!

In the first calculation i used actual PIV data, for the second, i made a guess, but you see my point.
If the efficiency of the red is the same as the efficiency of the blu (not mW per mA, but mWo per mWe - actual efficiency - the ratio of optical power OUT to electrical power IN), a switching driver will draw the SAME amount of curreent from the battery to reach the same power!

Now switching drivers sometimes have a slightly higher efficiency at higher output voltages, so the losses in the driver with a red will be a tiny bit higher. But if you use the 660nm AR coated acrylics, i see no reason not to get the same battery life with a 200mW red as with a 200mW blu..



EDIT: [highlight](Did i miss this, or did you add it?)[/highlight]

[quote author=jayrob link=1230765788/40#58 date=1231776158]I found one really high efficiency 6X diode that gives an incredible 220mW's at 192mA's through an AixiZ acrylic! This particular diode, set at 180mA's, would still be over 200mW's, even through an AixiZ acrylic lens!

That's a total freak, man!
You could not possibly find a better diode for a micro build!

I hope i find one like that! Did you by any chance plot it?

There is only one concern here. I noticed with some "high efficiency" 4x's, which put out way more power at the same current than others, that they took a higher voltage for that current!

So while mW per mA was higher, and made it seem high efficiency, mWo per mWe was not necessarily higher. And it is that, that matters in a case like this. That's why i'd love to see a PIV plot of this freak 6x.[/quote]


(I added it)
I love to see all or your calculations Igor! I call you 'The Scientist'...

Yes, I got some of those lenses and they are excellent, just like you said! He had them shipped to me direct from China. I don't know if he stocked more or not. But you can message the guy at e-bay and find out. Here's the link to contact the seller:
http://cgi.ebay.ca/Plastic-Collimat...ItemQQimsxZ20090220?IMSfp=TL090220123001r1848

About the freak 6X, I did not plot it. I just tested it at 192mA's, and when I saw that it was putting out 220mW's through the AixiZ acrylic lens, I just made some notes, and tucked that baby away for a future build.
Jay

 

[IgorT]

Re: Key Chain Blu-ray... With FlexDrive!

Yeah, mine always came from China, if i ordered from their "UK" or China shop..

But it's great news they are available again! It's good to have a cheaper but decent alternative to glass too. As long as it's coated.

Did you try one out in an open can yet?



As for the calcs, i'm just saying, that if it's possible to make a 200mW blu out of this neat micro host, it's just as possible, to make a 200mW red!
Because for a red, the switching driver will buck. It'll give the red 300mA but it will draw less than that from the battery. For the blu, the switching driver will boost. It will give the blu 180mA, but it will draw MORE than that..

So battery life won't be quite 30 minutes, since the driver will need to draw more than 180mA in both cases, but it will be no better or worse, than with the 200mW red.

 

[jayrob]

Re: Key Chain Blu-ray... With FlexDrive!

Yes, I tried the lens with my open can personal builds!

In fact, I no longer have any personal red builds with AixiZ acrylic...

I have a Kryton build with an open can red, that is running at 452mA's and now putting out 292mW's through this new AR coated acrylic lens. It was at 279mW's with an AixiZ acrylic...

That's interesting to know about the boost/buck differences using the FlexDrive. Somehow it doesn't make sense that a 300mA load will draw the same amount of power/battery life, as a 180mA load. But I trust this information from you Igor. Probably, if I do some comparisons, I will find that 'The Scientist' is correct!
Jay

 

[IgorT]

Re: Key Chain Blu-ray... With FlexDrive!

Awesome, eh? I can only get more power than that with glass! But for cheaper reds, that is a great lens!


As for the switching driver.. You are used to linear drivers (you must have made hundreds), where the current through the diode is the same as the current from the battery.  But this is exactly WHY they are called LINEAR..


The reason for the buck/boost differences is this:
Let's say you have a 6x at 200mA powered by a theoretical 100% efficiency boost driver (= electrical power out is same to power in, no losses).

The driver gets a Li-Ion for lunch. It has 4V available to it (under load, when battery full), and has to give the 6x 200mA..

But the 6x needs 5.3V for 200mA to flow through it! So the driver has to give the 6x 5.3V, and that will cause the desired current to flow (and then it will adjust this voltage, to keep current the same under all conditions, but that's another story called current regulation).

So, the driver only has 4V available, but has to give the diode 5.3V! So it boosts the voltage to 5.3V, and the diode pulls 200mA.

But if the driver was pulling 4V and 200mA from the battery and giving the diode 5.3V and 200mA, then it would not only be theoretical, but magical, since more power would come OUT, than goes IN! That's impossible. Even a 100% efficient driver can't do that!

So since it only gets 4V from the battery, but has to give the diode 5.3V, it has to compensate somewhere. And it does so by pulling more current, to make up for the difference.


Let's see.. Pout = 5.3V x 0.2A = 1.06W - the diode has to get 1.06W of electrical power. For a 100% efficient driver to put out 1.06W, it has to pull in 1.06W.

Since the driver only has 4V available for it, it has to pull in more current, to get 1.06W!
4V x I = 1.06W
I = 1.06W / 4V = 0.265A

So for a 100% efficient boost driver to put out 200mA at 5.3V, it has to pull 265mA at 4V!


But in reality, the best boost drivers are "only" 90% efficient. That means the 1.06W will be 90% of the power going in.
1.06W is 90% of 1.178W, meaning a non theoretical 90% efficient driver has to pull 1.178W to put out 1.06W.

So the realistic input curent calculation is this:
4V x I = 1.178W
I = 1.178W / 4 = 0.294A

So a 90% efficient boost driver has to pull 294mA at 4V, to feed a 6x 200mA at 5.3V. (if the diode voltage is different, so will be the current draw from the battery of course).



If you put a full battery in your personal 6x laser, for which you know the current setting, and then replace the tailcap with a DMM, you will see, that more current goes into the driver from the battery, than the current the diode is set to. If your 6x is set to 200mA, you will measure ~300mA current draw or maybe a bit more, in your personal 6x on a full Li-Ion (estimate based on the fact that it seems to have similar efficiency to my old 6x).. More as the voltage drops...

As the battery voltage gets lower and lower, the current drawn from the battery will HAVE to become higher and higher, to compensate for what is missing!


When you buck on the other hand (battery voltage higher than diode voltage), the driver has to pull less current, than it gives the diode - it's the other way around... If you measure the current draw of a FlexDrive powered open can from a full battery, you will see, it is less than the current the diode is set to.


Linear drivers pull the same current at a higher voltage, and put out the same current at a lower voltage. Power IN is much higher than power OUT, and the difference is discarded as heat. You could say, that linear drivers work by discarding everything but what the diode needs, as heat.

Switching drivers on the other hand, CONVERT the ratio of current and voltage, into what the diode needs, at a certain efficiency of course...



P.S. Now that i think of it, a near 300mW current draw is a lot for such a tiny battery! That's 3.3C! I don't know what their rated discharge capability is - probably 2C, but it sounds a little high. The higher the efficiency of the diode, the better for the tiny Li-Ion! (That doesn't mean i won't do it of course..  ;D)