BLuRay mod #2. 1xAA boost circuit.

[jake21]

just got my to charge2go

 

[IgorT]

just got my to charge2go  

Jake, it would seem the Charge2Go overdrives the normal Blue Rays, and is only safe as it is for the weird ones with a higher forward voltage..


In the last Group Buy, i recieved two different ones, and without testing them on a proper driver with current regulation first, and measuring the voltage, there is no way to know for sure which ones you have..


Since Chimo is getting around 78mW out of his Blue Ray, it is either a freak, or a different batch (i read there were shortages, and they put better ones in at one time). It is possible a normal Blue Ray would die instantly at these currents.


If you're gonna use this, you are most likely going to need a resistor between the diode and the circuit. But i have no idea what resistance.. I'm getting the DX versions tomorrow, but they will probably be completelly different, so my results won't really help much.



Chimo: What resistor would you recommend, to get the current down to a safe level?

 

[chimo]

[quote author=jake21 link=1199303658/30#32 date=1205195042]just got my to charge2go  

Jake, it would seem the Charge2Go overdrives the normal Blue Rays, and is only safe as it is for the weird ones with a higher forward voltage..


In the last Group Buy, i recieved two different ones, and without testing them on a proper driver with current regulation first, and measuring the voltage, there is no way to know for sure which ones you have..


Since Chimo is getting around 78mW out of his Blue Ray, it is either a freak, or a different batch (i read there were shortages, and they put better ones in at one time). It is possible a normal Blue Ray would die instantly at these currents.


If you're gonna use this, you are most likely going to need a resistor between the diode and the circuit. But i have no idea what resistance.. I'm getting the DX versions tomorrow, but they will probably be completelly different, so my results won't really help much.



Chimo: What resistor would you recommend, to get the current down to a safe level?[/quote]

It may be easier to shunt a little current away from the LD by putting it in parallel with it. A couple of hundred ohms should pull off around 25mA.

 

[IgorT]

It may be easier to shunt a little current away from the LD by putting it in parallel with it.  A couple of hundred ohms should pull off around 25mA.

You mean, like with a constant current source? I have used dozens of cell phone chargers, as power sources for other devices, and none of them had any kind of regulation whatsoever.. They just provide enough voltage for the built in circuitry inside the phone, to do all the charging..


Is there another reason, why not use a resistor in series, that i'm missing? (sorry if it's a stupid question)


Oh, and what is your current with the "freak" diode?

 

[chimo]

[quote author=chimo link=1199303658/30#34 date=1205422229]It may be easier to shunt a little current away from the LD by putting it in parallel with it.  A couple of hundred ohms should pull off around 25mA.

You mean, like with a constant current source? I have used dozens of cell phone chargers, as power sources for other devices, and none of them had any kind of regulation whatsoever.. They just provide enough voltage for the built in circuitry inside the phone, to do all the charging..


Is there another reason, why not use a resistor in series, that i'm missing? (sorry if it's a stupid question)


Oh, and what is your current with the "freak" diode?[/quote]

The "freak" is still working fine - it still has its mojo.

It's not a stupid question at all. Either resistoring method (series/parallel) should work OK. A series resistor should be a bit more efficient but the value will be a little harder to calculate if you don't know the LD's VI curve.

For a parallel resistor, if you estimate (or better yet, measure) the LDs voltage at around 5V, you can quickly work out that a 200ohm resistor across a 5V source will draw 25mA (= 25mA diverted away from the LD).

Paul

 

[IgorT]

It's not a stupid question at all. Either resistoring method (series/parallel) should work OK. A series resistor should be a bit more efficient but the value will be a little harder to calculate if you don't know the LD's VI curve.

For a parallel resistor, if you estimate (or better yet, measure) the LDs voltage at around 5V, you can quickly work out that a 200ohm resistor across a 5V source will draw 25mA (= 25mA diverted away from the LD).

You are right.. Without testing the LDs electrical characteristics, it would be impossible to know what resistor to use..

It makes much more sense this way. Thanks for the explanation!



BTW, i would still love to know, how much current you are "torturing" your mutant with.. Did you ever measure it? Or did you already answer, and i forgot? Oh, and do you know the voltage on it? It could help understanding which type it is.. Maybe it is from that replacement batch, when they used different ones because they ran out of the normal ones..

 

[chimo]

[quote author=chimo link=1199303658/30#36 date=1205445236]It's not a stupid question at all. Either resistoring method (series/parallel) should work OK. A series resistor should be a bit more efficient but the value will be a little harder to calculate if you don't know the LD's VI curve.

For a parallel resistor, if you estimate (or better yet, measure) the LDs voltage at around 5V, you can quickly work out that a 200ohm resistor across a 5V source will draw 25mA (= 25mA diverted away from the LD).

You are right.. Without testing the LDs electrical characteristics, it would be impossible to know what resistor to use..

It makes much more sense this way. Thanks for the explanation!



BTW, i would still love to know, how much current you are "torturing" your mutant with.. Did you ever measure it? Or did you already answer, and i forgot? Oh, and do you know the voltage on it? It could help understanding which type it is.. Maybe it is from that replacement batch, when they used different ones because they ran out of the normal ones..[/quote]

I didn't check the current. The board is fairly tight to get at the sense resistor. It's glued now so I don't want to take it apart.

 

[IgorT]

I didn't check the current. The board is fairly tight to get at the sense resistor.  It's glued now so I don't want to take it apart.

Oh, i see..

You thought it would be the same as with the other one, and didn't check, only to get a surprise, when pointing it at the LPM..


Is the power difference very noticable in the spot and the beam? Is it visible in the dark?

 

[chimo]

[quote author=chimo link=1199303658/30#38 date=1205451251]I didn't check the current. The board is fairly tight to get at the sense resistor.  It's glued now so I don't want to take it apart.

Oh, i see..

You thought it would be the same as with the other one, and didn't check, only to get a surprise, when pointing it at the LPM..


Is the power difference very noticable in the spot and the beam? Is it visible in the dark?[/quote]

The difference is quite noticable in the dot intensity. The beam is very, very faintly visible in total darkness but easy to see if I kick up some dust.

 

[IgorT]

You know what... The more i think of it, the more i have a feeling i had one like that in the first group buy..

The first one was very dim at 39mA and i was dissapointed. The second one was brilliant, and so bright, that i thought the first one is bad.

Then i was looking at the beam, and went to reposition it, and when i touched it, it lost pretty much all it's brightness, and became only as bright as the first one..

It was ESD, because i was powering the driver from a PSU. I thought it would be safe with a cap directly on it, and in the circuit, but i was wrong. From that moment on, i'm only using battery power, and i haven't lost a diode since then..


Anyway, seems like we both got one normal and another stronger one, because they were out of the regular diodes and replaced them with better ones at a certain time, or so i heard..

Unfortunatelly, this makes me worried, that i will only get two regular ones in the current group buy...


Untill now i thought, that all the normal ones were that bright, unless there is something wrong with them. Guess i was wrong. I could be in for a dissapointment..

 

[IgorT]

I just recieved the DealExtreme versions of the Charge2Go.

I thought i ordered three different models, but it would seem i only ordered two, one of the models in two different colours and the other in a different colour, than depicted on the page..

And even so, they all look exactly the same, except for one having a battery drawn on it. The top looks different than the DX pictures, and much closer to the original Charge2Go.

I have a feeling, they are all exact copies. Need to check the PCBs, but i didn't notice any differences so far.


They are easy to take appart completelly, and only the battery cover is sometimes hard to screw on, if you don't align it properly.


With a full battery they put out 5.72V without a load and 5.63V with an empty battery, but in this case without any current behind it..

From what i measured, they consume 1mA or less with no load, which is good. I've seen a DX boost circuit, that consumes more than 1A without a load.


Since i'm going to another city for the weekend i won't be able to test them right now. More info on monday.

 

[IgorT]

It turns out i won't see my girlfriend for another week. It was crazy at work the last month and it's still not over.

I'm gonna use one of these Charge2Go clones to host and power a red burner with current regulation from a single AA Ni-MH cell. I did some measurements, and i have to say i'm really impressed with the currents these tiny circuits are capable of. I wish i could make the 3410 this small...

 

[chimo]

OK, my curiosity got the better of me and I had to find out what current the second BR LD was running at.

Now, before I do that, I just want to say that the output at 70-80 was amazing. It would actually burn wood (bare pine). It would light a match instantaneously.

OK, here it is (insert drum roll):

I inserted a 1% 0.1 ohm resistance and measured the voltage drop across it to calculate the current.

The current was a mere 110mA and the voltage across the BR LD was 5.43V.

Although the power of a BR at 70+mW is amazing, I decided not to put the poor little BR LD through any more torture so I inserted a 15ohm series resistance to drop the current down to 45mA. The output power is now 16mW.

 

[IgorT]

That actually sounds like a normal power for a blue ray at that current.

I'm very surprised about that.


A mere 110mA current? That's nothing. Mine take twice that.. Of course nothing much comes out on the other end...


BTW, the DX Charge2Go clones use completelly different circuits. I haven't found the datasheets yet, so i don't know what they are capable of exactly, but i connected one of my sick blue rays directly to it, and it lit up slightly less than it does at 220mA. I measured the current at 150mA.

At DVD voltages, they are capable of putting out >600mA.. I'm gonna try combining this with an AMC, and see what happens..


Would be great if i could find a datasheet tho, to see if the output is adjustable. As they are, they put out an almost exactly the same open circuit voltage as all the wall wart chargers i have converted for other uses so far.

 

[chimo]

Cool picture time.  Here's a shot of my Bluray's beam bouncing around inside my watch crystal.  Entry from the right, exit on the left.

 

[chimo]

Post a macro shot of the driver board. You never know...

That actually sounds like a normal power for a blue ray at that current.

I'm very surprised about that.


A mere 110mA current? That's nothing. Mine take twice that.. Of course nothing much comes out on the other end...


BTW, the DX Charge2Go clones use completelly different circuits. I haven't found the datasheets yet, so i don't know what they are capable of exactly, but i connected one of my sick blue rays directly to it, and it lit up slightly less than it does at 220mA. I measured the current at 150mA.

At DVD voltages, they are capable of putting out >600mA.. I'm gonna try combining this with an AMC, and see what happens..


Would be great if i could find a datasheet tho, to see if the output is adjustable. As they are, they put out an almost exactly the same open circuit voltage as all the wall wart chargers i have converted for other uses so far.