FS: >110mW PHR, >140mW 4x & >170mW 6x Blu-Rays

[FrancoRob]

....
Otherwise, do you need the raw PIV data for your compilation?

YES!:yh:

 

[IgorT]

A very nice diode indeed! 414mW's at 290mA's (405-G-1) is sweet! And I noticed that the forward voltage is low too! Compared to Dave's diode, which is up around 6 volts at that current...

Yes, i was wondering about that! I was asking myself "Where the hell is the voltage everyone is talking about?!?" :thinking:

This particular diode has a Vf similar to 6x's altho at a higher current, making me think that this current is survivable for a long enough time.
I mean, the voltage did not go above the limits proposed by the various datasheets, and i usually take this as a good sign.....

This particular diode could even be powered by a FlexDrive without overloading it...

But we know that Vf's vary quite a bit among diodes of the same type... Maybe this one is unusual? Or are the high ones unusual?



One very important thing the lower Vf means is, that this diode REALLY IS a freak! It's actual efficiency is MUCH higher than of those with higher Vf's... In practical terms, this means it requires less electrical power to reach the same (or even higher) optical power.

EDIT: Another thing this means is, that it heats up LESS during operating! Since the difference between the power going in and the power going out is LOWER! Less gets wasted as heat! Heat is the difference between power IN (electrical) and power OUT (optical). Both are measured in Watts.

In fact, even the slope efficiency is high if i am not mistaken! It's a damn good diode! :yh:
I bet if i make myself a 203BK one day, i won't be so lucky!



But i still feel blessed, being allowed to play with it for a night! :drool:
Sleeping postponed again.

Just kidding Franco, i won't abuse it... Too much...

But i would like to take some beamshots, power measurements at different temperatures, and maybe a power stability graph? If only i could remember where i put that cable that is... :thinking:




Jay: You have one at almost the same current and power, right? Do you perhaps know it's Vf?

 

[IgorT]

YES!:yh:

Hehe, obsolete question, eh?

Sending email...

 

[jayrob]

Yes, i was wondering about that! I was asking myself "Where the hell is the voltage everyone is talking about?!?" :thinking:

... Jay: You have one at almost the same current and power, right? Do you perhaps know it's Vf?

I did not graph the voltage readings, but I did measure the voltage at 292mA's, and I mentioned it in a post somewhere.

I didn't write it down, but I know it was not 6 volts. 5.7 rings a bell...

 

[IgorT]

I didn't write it down, but I know it was not 6 volts. 5.7 rings a bell...

In that case it's just standard deviation.... It sounds about right.. GGWs vary quite a bit as well.


I measured 5.58V at 290mA, maybe these diodes have their Vf specified as 5.5-6V. I've seen some datasheets like that. Others say 5-5.5V...
Or maybe these are specced as 5-5.5V and we are driving them too hard. In that case i am happy that i did not go too far above 5.5V...

In any case, more efficiency is never a bad thing.



But where is the problem with FlexDrives and 203BK's then?

I thought the problem was, that this diode needed 7V (several people told me so)! Now that would be bizzare! No datasheet ever said more than 6V MAX!

At 7V the FlexDrive could not keep up anymore, that is true, but from what i'm seeing here, FlexDrives could power the 203BK diodes to ~400mW easily. Or at least most of them....


Or did the 7V happen at 500mA?!? That could simply be an indication, that the diode is being murdered rapidly....

Or did i confuse diodes again?

 

[jayrob]

Dr. Lava had posted that he would recommend only 6 volts, which is about 300mA's on some of the BDR-203 diodes...

But I know of at least one person running a FlexDrive in a Pocket Mini/8X at 360mA's.

I wonder what would happen if the voltage that the diode was wanting could not be delivered by the driver? Would is just not give anymore power than a certain point, or would the driver shut down?

At any case, I would imagine that Dr. Lava gave a fairly conservative recommendation...

 

[IgorT]

FS: >130mW PHRs, 185-250mW 6x Blu-Rays, 300-400mW BluRays on request!

Dr. Lava had posted that he would recommend only 6 volts, which is about 300mA's on some of the BDR-203 diodes...

I see.. Officially the FlexDrive should not be boosting above 5.5V, but manages to go to 6V as per the datasheet's Absolute Max Ratings...

Problems appear, when the chip tries to boost higher than that, in order to reach the set current. It can burn itself out. Same as if you power a v1 Flex without a load! Altho usually they can go a bit higher than they are rated for, but reliability is not 100% anymore (devices are always made to withstand more than needed, so that they would be more reliable when used within the official limits - that's also what allows us to push diodes)...



But i'm thinking about another possible explanation for the strict limit. The reason could be a different Zener on the latest FlexDrives..

I once discussed the no-load issue with Lava, asking if he has a Zener diode in reverse on the output of his v1's, since people would eventually power them up without a load, either by accident or lack of knowledge (like trying to measure if the voltage is good for their diode)....

He did put a Zener on all later versions, and what it does - it starts conducting the current the driver is set to, if the voltage crosses a certain point (where that point is, depends on the Zener voltage) - the Zener opens and acts as a load in that case... Then at least the boost chip doesn't commit suicide trying to pass current through air!


I don't know the voltage rating of the Zener Lava uses nowadays, but he said it was 7V for the earlier versions... Altho he later mentioned that he was going to reduce it closer to 6V cos 7V is still too hard for the chip.

Maybe the lowering of the Zener's voltage to barelly above 6V is the reason for the strict 6V limit? If so the two diodes would start competing for the current, if the Vf of the laser diode was too high (a common Zener that comes to mind is 6.3V, which might be the ACTUAL limit).

But I know of at least one person running a FlexDrive in a Pocket Mini/8X at 360mA's.

Well, either his diode (is it a 203BK?) is similar to Franco's and has a lower Vf, or his FlexDrive has a chip capable of a little more, due to standard manufacturing tolerances...

I wonder what would happen if the voltage that the diode was wanting could not be delivered by the driver? Would is just not give anymore power than a certain point, or would the driver shut down?

Actually, neither. It would try to boost the voltage high enough to reach that current, but could damage itself in the process.

The problem comes from the constant current. The diodes require a certain voltage to reach the set current. Regardless of what voltage is needed, the chip will always try very hard to reach it - boosting as high as it possibly can, trying to push the set current through the load...

If the voltage at that current is too high, the chip will push itself too hard, potentially frying itself. They actually go up in smoke when this happens!

With FlexDrives, which can't boost too high anyway, this is not always immediatelly catastrophic.
But it's not good for them either! It can cause permanent damage to the chip, causing it to gradually start malfunctioning or stop working completelly.


I haven't killed a FlexDrive this way yet, but i did kill several of my drivers by accidentally powering them up without a load (an interruption in the dummy load circuit i overlooked). The chip would go up in flames in half a second! This is because it's made to boost as high as 25V, but it fries itself, when it tries to go over 30V, in a feeble attempt to push current through air.. Due to the higher voltage it is capable of, it would kill itself much faster if powered without a load (if it had no protection).


With linear drivers this is not a problem. No load, and they simply peak somewhere below their input voltage. But boosters... Well, they can boost! And constant current boosters try to force current through whatever load is there. To create current, you need voltage, so what the driver does, when it "notices" that the set currrent is not flowing - it increases the voltage! More and more, until the set current is reached OR the driver is dead. Because when the "load" is air, it would take ~2000V to breach the gap between the two output pins (altho even then no current would be flowing, just sparks flying)!


So unless there is a load or some sort of protection, constant current boosters often kill themselves upon power-up. It's just the way they work - they are just trying to do what they are made to do, but with an incomplete circuit - a current source circuit is never complete without the load!

It's a completelly different thing from a voltage source, which does it's thing regardless of the presence of a load.




If on the other hand, the voltage was just slightly outside the chips limit, most of the chips would still be able to power the diode to full current for a while (some even without a glitch - manufacturing tolerances), but many would "suffer" while doing so, slowly damaging themselves until they would eventually stop working (kill themselves) or potentially even "go crazy" (and maybe even kill the diode)..

At any case, I would imagine that Dr. Lava gave a fairly conservative recommendation...

That i am sure of. He knows that Vf's vary, and that the majority of people don't know the Vf of their diode at their desired current/power.
So he probably went for the safest bet - a current where he was sure none of the 203BK's would go over 6V. (Maybe the real limit really is 6.3V - i should test it)



But if you simply test the diode from a linear driver FIRST, set to the desired final current and then measure the voltage across the diode and it's 6V OR LESS it can safelly be powered by a FlexDrive....

EDIT: This measurement should be performed on a COLD diode! The linear driver should probably be away from it so it doesn't heat up the diode. Cold diodes have a higher Vf, and you want to know the max...

 

[Sam7]

a mod might as well make this thread a sticky.

 

[Darkarmyofone]

I KNEW these diodes were at LEAST worth the money, IgorT, It seems Franco's diode is either an AWSOME freak, or it is just from a good batch,

I USUAiLLY run the 203's at 265mA to be safe.

And i saw you achieved over 400mW after a 405-G1 at quite a low current! Thats awsome for franco!

I have a few 203's and SF-AW's im going to be doing extensive testing on "when the laserbee I arrives wich should be ANY day" coming straight from Jerry though, so has to go through canada customs"

But anyways, VERY interesting. I hope i can contribute somehow

Dark

 

[IgorT]

They definitelly are worth the money...

If i had it i would get one for myself right now! But unfortunatelly i just spent almost $400 on destructive testing of multiple different useless (more or less) diodes over the last month alone...


Oh well, i guess a personal 8x will have to wait...

At the moment it seems mine will be the fourth 203BK i'll make.
Unless Traveller suddenly requests his bonus-build... Then it'll be the fifth - if i'm lucky!

 

[Prototype]

Can't wait to see those greens Igor.

Edit: 120th post, I don't know why I keep doing this

 

[IgorT]

Can't wait to see those greens Igor.

Me neither! :angel: They are still in prototyping stage...


Well, actually i just need to select a short enough module, to get it in the head of my host, and allow a full length protected 14500 battery in (backwards!!)...


Also, i will replace the usually non-working Chinese wanna-be "drivers" with real ones, which will keep starting power the same over the entire battery voltage range (same power on empty as on full battery - a concept the Chinese can't seem to grasp for some reason)... :thinking:

Well, some rare Chinese manufacturers do, just not the affordable ones...

 

[FrancoRob]

Igor:
In spite of the fact that I cannot understand where, in a 24 hours day, you'll find the time to do also this:bowdown:, I am enthusiast of this decision!
I'm sure that the Spartans I tried from DL failed due to an insufficient driver design....

For a result at a standard IgorT quality level (that is, really high) you'll need to find green modules which allow also to control the divergence.....

 

[IgorT]

Igor:
In spite of the fact that I cannot understand where, in a 24 hours day, you'll find the time to do also this:bowdown:, I am enthusiast of this decision!
I'm sure that the Spartans I tried from DL failed due to an insufficient driver design....

Well, i already have suitable replacement drivers, they are round and flat and won't occupy more than 3mm of the host's length. What they will do, is keep the current constant!

The real problem is finding short enough modules. Just when i thought one was available, Traveller informed me it's pathetic (the Chinese measured it at 180mW, he measured it at 70 or so and dropping fast, not to mention the TEM - it was bad, i'm getting it for testing, to see if anything could be done).

I want a module that is TEM00, stable and if possible at all, has decent divergence.

I already know that most of the drivers don't work, so i don't have any requirements as to that, besides, with these greens it's the drivers that occupy as much as half of the total module length! It's better they don't work or i'd be tempted to try using them...

Without that long driver it'll be much easier for me to get a long battery in a tiny host with a green!


However the developement of my greens may be postponed a little, due to PP reasons. I'll have to test multiple modules, and i already wasted too much money this month on diode testing alone.



Spartans from DL? Are those not CNI models (not sure)?
CNI makes AWESOME common anode drivers! Very low dropout voltage (as low as 0.3-0.4V) and incredible current stability!

But their baseball-bat lasers, especially the high power ones are not that good....
They are "Near TEM00" - a collection of multiple blobs trying to form a spot, but sometimes/often failing...

 

[FrancoRob]

Igor:

What kind of module do you need? I mean, only a nude module or a pointer from which you can take out the module? If the second is the case, I have a CNI good pointer just checked for the P.O.: with 2 exhaust AAA eneloop batteries it gives a steady 123mW, while with fresh batteries it gives 160mW...; the divergence looks a little bit better than my Viper 95.
I know, it's a damned good pointer, but the idea to have it improved in one of your hosts is fascinating me (maybe with no more duty cycle)... on the other side yes, a green beam is really nice and easy to see, but now I know that nothing burns better than a 405nm...and the violet beam has his great fashion too......

Concerning the DL Spartan, I don't know about the module (maybe CNI manufactures it), but the host is specifically DL.

 

[IgorT]

Ideally i'd need a 25mm module, so there's room left for my common-anode driver. That way everything could be in the head, and a protected 14500 could be used.


But CNI pens have MUCH longer modules than that! I took mine appart, to put it into a 30mW Romisen greenie host, which has an absurd amount of heatsinking for 30mW (while actually putting out 14mW on a good day), but is perfect for higher powers in small form!


Check it out.. This is what i can make out of a CNI pen (or certain modules).. With some help from Jayrob of course.

It's no longer than my "Classic" Romisen host, but the big aluminum head gives the thing some decent heatsinking!