Magic resistor pics and start of My light page
- Thread starter SKYWLKR
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Burnt_Retinas
Enlightened
Huh, it's own page?
I better pull my finger out and find those pic links unreliably hosted by imagestation within the MR-X thread.
Thanks for allowing me to host them where you have space /ubbthreads/images/graemlins/smile.gif
Now for a mull through the site....
Much appreciated,
Chris
I better pull my finger out and find those pic links unreliably hosted by imagestation within the MR-X thread.
Thanks for allowing me to host them where you have space /ubbthreads/images/graemlins/smile.gif
Now for a mull through the site....
Much appreciated,
Chris
Maybe you could put up this useful info too? Would be great.
http://tjtech.org/~CPF/darkzero/misc/mr_current-adjustment.jpg
http://tjtech.org/~CPF/darkzero/misc/mr_current-adjustment.jpg
krutzbeuazen
Newly Enlightened
Hey SKYWLKR,
nice FLashlights/Mods, good work!
what exactly can your "magic resistor" circuit do?
uuuhm, lemme guess.. it changes its resistance depending on the input, like a constant voltage supply?
is Vin and/or Vout adjustable? how much minimum voltagedrop or difference Vin/Vout does it have? and, most important for me, since mine would be big and ugly so i could only -if at all- use one, how much current can it deliver?
thanks in advance, probably this was all discussed somewhere else earlier, just didnt find anything yesterday about it..
krutz
nice FLashlights/Mods, good work!
what exactly can your "magic resistor" circuit do?
uuuhm, lemme guess.. it changes its resistance depending on the input, like a constant voltage supply?
is Vin and/or Vout adjustable? how much minimum voltagedrop or difference Vin/Vout does it have? and, most important for me, since mine would be big and ugly so i could only -if at all- use one, how much current can it deliver?
thanks in advance, probably this was all discussed somewhere else earlier, just didnt find anything yesterday about it..
krutz
Burnt_Retinas
Enlightened
krutz, if I can call you that for short...
I hope Skywlkr doesn't mind me answering on his behalf, I believe he is in need of sleep (yet another flashlight mod).
Yes, MR changes it's resistance depending on I/P volts v. O/P needs.
It is intended to fit in the niche where high power is required, yet the battery volts are soooo close to LED voltage that a buck or boost is not an option - eg a 5W from 6 X NiMH/2 X Li-Ion. SEPIC's are hardly the choice for high power AND efficiency. It turns out it is also very flexible in accepting Alkalines, Lithium's, Li-Ions (2 X) for such applications with unprecedented efficiencies - close to 100%, that switcher's can't reach. This only applies for certain cell combo's vs. 5 W LED though as per stated. If you have a lot more volts than LED then go a buck converter, much less volts go a boost.
Vin/out adjustable - It's constant current, not voltage; and YES it's adjustable to over 2 A. Recommended I/P voltage - say up to 2 - 3 volts above the 5W you intend to drive.
Vin/Volt difference - bugger all. Consider it as almost like just a piece of wire when it is hard on as battery volts nears LED voltage. It's equivalent to just over 15 milli ohms when hard on, and provides a LED output to indicate this 'direct drive' status.
Chris
I hope Skywlkr doesn't mind me answering on his behalf, I believe he is in need of sleep (yet another flashlight mod).
Yes, MR changes it's resistance depending on I/P volts v. O/P needs.
It is intended to fit in the niche where high power is required, yet the battery volts are soooo close to LED voltage that a buck or boost is not an option - eg a 5W from 6 X NiMH/2 X Li-Ion. SEPIC's are hardly the choice for high power AND efficiency. It turns out it is also very flexible in accepting Alkalines, Lithium's, Li-Ions (2 X) for such applications with unprecedented efficiencies - close to 100%, that switcher's can't reach. This only applies for certain cell combo's vs. 5 W LED though as per stated. If you have a lot more volts than LED then go a buck converter, much less volts go a boost.
Vin/out adjustable - It's constant current, not voltage; and YES it's adjustable to over 2 A. Recommended I/P voltage - say up to 2 - 3 volts above the 5W you intend to drive.
Vin/Volt difference - bugger all. Consider it as almost like just a piece of wire when it is hard on as battery volts nears LED voltage. It's equivalent to just over 15 milli ohms when hard on, and provides a LED output to indicate this 'direct drive' status.
Chris
krutzbeuazen
Newly Enlightened
/ubbthreads/images/graemlins/ooo.gif ooooh my god!
after weeks of looking around for acceptable circuits, this sounds unbelievable!
almost no resistance and no minimum voltagedifference? constant current? even adjustable? (with other Q1 i guess) more than 2 Amp?
its perfect! flawless! i dont think i ever was that impressed of "just a circuit" yet! ;-)
so its all in SMD, and the Q1 somewhere in the heatsink/hotlips..?
lets see how many of these parts are absolutely 100% impossible to get over here.. not thinking about the days it will take untill i learned how to solder SMD ^^
wow.. looks like i'll have a busy time now..
you made my day!
krutz, smiling
after weeks of looking around for acceptable circuits, this sounds unbelievable!
almost no resistance and no minimum voltagedifference? constant current? even adjustable? (with other Q1 i guess) more than 2 Amp?
its perfect! flawless! i dont think i ever was that impressed of "just a circuit" yet! ;-)
so its all in SMD, and the Q1 somewhere in the heatsink/hotlips..?
lets see how many of these parts are absolutely 100% impossible to get over here.. not thinking about the days it will take untill i learned how to solder SMD ^^
wow.. looks like i'll have a busy time now..
you made my day!
krutz, smiling
Yes I was tired and needed sleep badly. /ubbthreads/images/graemlins/eek.gif /ubbthreads/images/graemlins/eek.gif /ubbthreads/images/graemlins/mecry.gif
I just wanted to Add I have no Part in the MR circuit (not that I would'nt want to take credit)... I am just hosting the info and a made a small page to navigate it.
I have yet to build nor even see one in person.
It does indeed seem like a Magic Part and indeed it is (well almost) but it does have it's limits as Burnt_Retinas (the MR Creator?)said above.
I do appreciate the complimnts on my mods.
(have you seen the Polished aluminum one that deprived me of such sleep? It didnt take a whole lot of time but I started late and just had to finish one last part...wait one last one more,and then it was done...except it needed a web page....wait that lanyard looks like it would work....)
But I am happy with it ,and did'nt take to many short cuts on it and none that would affect functioning, even as late as it was. the next one on the same body will have a LUX III and a lot more finishing effort into it.
I just wanted to Add I have no Part in the MR circuit (not that I would'nt want to take credit)... I am just hosting the info and a made a small page to navigate it.
I have yet to build nor even see one in person.
It does indeed seem like a Magic Part and indeed it is (well almost) but it does have it's limits as Burnt_Retinas (the MR Creator?)said above.
I do appreciate the complimnts on my mods.
(have you seen the Polished aluminum one that deprived me of such sleep? It didnt take a whole lot of time but I started late and just had to finish one last part...wait one last one more,and then it was done...except it needed a web page....wait that lanyard looks like it would work....)
But I am happy with it ,and did'nt take to many short cuts on it and none that would affect functioning, even as late as it was. the next one on the same body will have a LUX III and a lot more finishing effort into it.
krutzbeuazen
Newly Enlightened
@SKYWLKR:
yes, that flashlight(s) look nice!
well, i´m still far away from flashlight bodies, still at the basics like lightsource, energysource and -you guess it- electronics in between..
btw, how do your "flood" ones work? resistor?
from other "work" i know for sure how easily you could spend hours, days or worse on a project, to get it perfect. details others wouldnt even notice without telling them ;-)
@Burnt_Retinas:
amazing.. i wouldnt have believed parts as the IRF3703 would even be possible to build, and now there are less than 50 hits at google. one single ingermany. no, its no shop.
you dont happen to have bought 10.000 pcs of them and want to get rid of a handfull? ;-)
ah. australia. other side of the earth. no, i´m not surprised by this.
*dumping a big pile of plans into the trash, looking for some more pens and paper*
krutz
yes, that flashlight(s) look nice!
well, i´m still far away from flashlight bodies, still at the basics like lightsource, energysource and -you guess it- electronics in between..
btw, how do your "flood" ones work? resistor?
from other "work" i know for sure how easily you could spend hours, days or worse on a project, to get it perfect. details others wouldnt even notice without telling them ;-)
@Burnt_Retinas:
amazing.. i wouldnt have believed parts as the IRF3703 would even be possible to build, and now there are less than 50 hits at google. one single ingermany. no, its no shop.
you dont happen to have bought 10.000 pcs of them and want to get rid of a handfull? ;-)
ah. australia. other side of the earth. no, i´m not surprised by this.
*dumping a big pile of plans into the trash, looking for some more pens and paper*
krutz
Burnt_Retinas
Enlightened
Skywlkr,
Lost sleep over a flashlight mod - now I know that feeling /ubbthreads/images/graemlins/sleepy.gif
There's alway's just one more thing you can do before going to bed. The next time you check the time it's early AM. From the results to-date, you look like you're on the fast track to some great flashlights. Looking Good /ubbthreads/images/graemlins/smile.gif
***edited*** No, double edited! I'll blame sleep deprivation. No change if you didn't read original.
Krutz,
Over 2 A - yes. The FET used is a real overkill, but I just had to have it go to almost zero for such combo's as 6 X NiMH into a 5W LED. As much current as you want but watch the power dissipation and think wisely re host temp vs. runtime when using batteries much above the Vf of the LED. A switching circuit is best for those occasions where you have several volts above LED considering the voltage as the cells discharge.
Oh, yes, the FET is under the MR and attached to Hotlips. I do have some, but it's not worth the hassle of organizing payment for a one-off low cost part. If you PM me an address, I'll just send one postage paid - in the spirit of CPF.
Chris
Lost sleep over a flashlight mod - now I know that feeling /ubbthreads/images/graemlins/sleepy.gif
There's alway's just one more thing you can do before going to bed. The next time you check the time it's early AM. From the results to-date, you look like you're on the fast track to some great flashlights. Looking Good /ubbthreads/images/graemlins/smile.gif
***edited*** No, double edited! I'll blame sleep deprivation. No change if you didn't read original.
Krutz,
Over 2 A - yes. The FET used is a real overkill, but I just had to have it go to almost zero for such combo's as 6 X NiMH into a 5W LED. As much current as you want but watch the power dissipation and think wisely re host temp vs. runtime when using batteries much above the Vf of the LED. A switching circuit is best for those occasions where you have several volts above LED considering the voltage as the cells discharge.
Oh, yes, the FET is under the MR and attached to Hotlips. I do have some, but it's not worth the hassle of organizing payment for a one-off low cost part. If you PM me an address, I'll just send one postage paid - in the spirit of CPF.
Chris
krutzbeuazen
Newly Enlightened
Chris,
wow! learn something new every day! wouldnt have believed things like FETs do exist. looks like the most useful invention ever, for driving LEDs!
okay. i found some specs on yours. says 30v at 210A. now i get the meaning of your "overkill", i think. *falls from chair*
two more questions, before i lock myself in my lab again hehe
- what for is R5: the 15mR resistor between the FET and Vin?
- what is the min/max voltage the circuit can deliver to the FET (as "signal")? i read 11.25mV for 750mA and 22.5mV for 1.5A? depending on the range it can fit, it shouldnt be that hard to find a suitable FET for your circuit?
(what do you think your setup would deliver as output maximum right as it is?)
i cant wait to get my hands on the parts! ah, will have to try discrete parts first unfortunaly.. if i will manage SMD at all, someday.. dont even have the right tools for it yet..
again, thank you very much for all your help and time you spend!
krutz
wow! learn something new every day! wouldnt have believed things like FETs do exist. looks like the most useful invention ever, for driving LEDs!
okay. i found some specs on yours. says 30v at 210A. now i get the meaning of your "overkill", i think. *falls from chair*
two more questions, before i lock myself in my lab again hehe
- what for is R5: the 15mR resistor between the FET and Vin?
- what is the min/max voltage the circuit can deliver to the FET (as "signal")? i read 11.25mV for 750mA and 22.5mV for 1.5A? depending on the range it can fit, it shouldnt be that hard to find a suitable FET for your circuit?
(what do you think your setup would deliver as output maximum right as it is?)
i cant wait to get my hands on the parts! ah, will have to try discrete parts first unfortunaly.. if i will manage SMD at all, someday.. dont even have the right tools for it yet..
again, thank you very much for all your help and time you spend!
krutz
Burnt_Retinas
Enlightened
krutz,
Not wanting to hijack the thread, if you have more questions, please PM me. To answer the two you have:
R5 is the current sense resistor between the source of the FET and ground as per the circuit.
Re Min/Max voltage - keep voltage within a couple of volts above the LED (an LV LED). If you have a non-LED application it may also be suitable way beyond that, but PM me with the application for an answer.
Note - the circuit components were chosen so discrete parts CAN be used for those with the space eg a Mag. All parts chosen are available in discrete form. You really have struck gold!
Chris
Not wanting to hijack the thread, if you have more questions, please PM me. To answer the two you have:
R5 is the current sense resistor between the source of the FET and ground as per the circuit.
Re Min/Max voltage - keep voltage within a couple of volts above the LED (an LV LED). If you have a non-LED application it may also be suitable way beyond that, but PM me with the application for an answer.
Note - the circuit components were chosen so discrete parts CAN be used for those with the space eg a Mag. All parts chosen are available in discrete form. You really have struck gold!
Chris
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