Micro-Drive laser driver by rkcstr

[amkdeath]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

haha, yeah, it is a decent side job since my actual one pays hardly anything ($9/hr). Selling these helped me pay my rent this month

Dunno what will come next. I'm not sure how long I'll continue to sell them because of school as I may be getting busy, at least come 2009, then I won't have much spare time at all.

I would like to make something more efficient and I like the design woop, airy52 and toked323 were working on, though I know woop wanted his to be a sort of open source driver, though I'm not sure a lot of people would be able to make it themself. Also, a sepic design, which I know IgorT has been making one for his lasers, though the parts cost is kinda high, probably along the lines of the lavadrive.

Anyway, for the driver you have, a 12.4ohm should put out about 100mA, but the previous design may have some slight drop in current due to oscillation (its cleaned up by the output cap), so the output may possibly be dropping to slightly above 90mA, which 60mW sounds reasonable. I have a diode that put out about 65-70mW at 100mA but puts out 110mW at 125mA, so its not quite linear.

i see, so would it be better if I installed an output cap?

 

[sk8er4514]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

[quote author=rkcstr link=1206947255/348#351 date=1215547010]haha, yeah, it is a decent side job since my actual one pays hardly anything ($9/hr).  Selling these helped me pay my rent this month  

Dunno what will come next.  I'm not sure how long I'll continue to sell them because of school as I may be getting busy, at least come 2009, then I won't have much spare time at all.

I would like to make something more efficient and I like the design woop, airy52 and toked323 were working on, though I know woop wanted his to be a sort of open source driver, though I'm not sure a lot of people would be able to make it themself.  Also, a sepic design, which I know IgorT has been making one for his lasers, though the parts cost is kinda high, probably along the lines of the lavadrive.  

Anyway, for the driver you have, a 12.4ohm should put out about 100mA, but the previous design may have some slight drop in current due to oscillation (its cleaned up by the output cap), so the output may possibly be dropping to slightly above 90mA, which 60mW sounds reasonable. I have a diode that put out about 65-70mW at 100mA but puts out 110mW at 125mA, so its not quite linear.

i see, so would it be better if I installed an output cap?[/quote]
from my understanding of capacitors, it wouldn't help give you any more power to the diode, would just clean up the voltage wave going to it by charging it's stored voltage with some of the driver's voltage so that the voltage spike doesn't go as high (& low as it will oscillate for a while then even out). so it would be better in that it would be safer for the diode, but not give it more power as it seems that you want. you could get a resistor pack from rkcstr and try to make the driver output a little more by changing up the values, check out his spreadsheet to see the different combinations and current outputs.

good luck

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

[quote author=rkcstr link=1206947255/348#351 date=1215547010]haha, yeah, it is a decent side job since my actual one pays hardly anything ($9/hr). Selling these helped me pay my rent this month

Dunno what will come next. I'm not sure how long I'll continue to sell them because of school as I may be getting busy, at least come 2009, then I won't have much spare time at all.

I would like to make something more efficient and I like the design woop, airy52 and toked323 were working on, though I know woop wanted his to be a sort of open source driver, though I'm not sure a lot of people would be able to make it themself. Also, a sepic design, which I know IgorT has been making one for his lasers, though the parts cost is kinda high, probably along the lines of the lavadrive.

Anyway, for the driver you have, a 12.4ohm should put out about 100mA, but the previous design may have some slight drop in current due to oscillation (its cleaned up by the output cap), so the output may possibly be dropping to slightly above 90mA, which 60mW sounds reasonable. I have a diode that put out about 65-70mW at 100mA but puts out 110mW at 125mA, so its not quite linear.

i see, so would it be better if I installed an output cap?[/quote]

I definitely recommend having an output cap on there (which it came with, or did you remove it?). The old ones you have can be stabilized using a tantalum cap across the resistors (between adj and out pin on the regulator IC) or from the adj pin to ground. I use a 10uf cap in my drivers now which corrects that issue. You can also try a large ceramic cap, but the tantalums are better. I can put a few in with your order when I send it, if you want.

 

[amkdeath]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

[quote author=amkdeath link=1206947255/348#352 date=1215547390][quote author=rkcstr link=1206947255/348#351 date=1215547010]haha, yeah, it is a decent side job since my actual one pays hardly anything ($9/hr). Selling these helped me pay my rent this month

Dunno what will come next. I'm not sure how long I'll continue to sell them because of school as I may be getting busy, at least come 2009, then I won't have much spare time at all.

I would like to make something more efficient and I like the design woop, airy52 and toked323 were working on, though I know woop wanted his to be a sort of open source driver, though I'm not sure a lot of people would be able to make it themself. Also, a sepic design, which I know IgorT has been making one for his lasers, though the parts cost is kinda high, probably along the lines of the lavadrive.

Anyway, for the driver you have, a 12.4ohm should put out about 100mA, but the previous design may have some slight drop in current due to oscillation (its cleaned up by the output cap), so the output may possibly be dropping to slightly above 90mA, which 60mW sounds reasonable. I have a diode that put out about 65-70mW at 100mA but puts out 110mW at 125mA, so its not quite linear.

i see, so would it be better if I installed an output cap?[/quote]

I definitely recommend having an output cap on there (which it came with, or did you remove it?). The old ones you have can be stabilized using a tantalum cap across the resistors (between adj and out pin on the regulator IC) or from the adj pin to ground. I use a 10uf cap in my drivers now which corrects that issue. You can also try a large ceramic cap, but the tantalums are better. I can put a few in with your order when I send it, if you want.
[/quote]


ok thanks, Yea, I modified one of the boards that didnt have one on it to start with.

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

Wow... I FINALLY got caught up on my orders from while I was gone and those from this week!

All in all, that's 81 drivers and 11 test loads

Some orders went out today and the rest of the orders (made up until right now) will go out tomorrow. If you received a Paypal shipping notice, take a look at the "ship date", if it has today's date (7/11/08), it went out today, otherwise it will say 7/12/08 and be in the mail tomorrow.

Oh, and I'm just about run out of parts... I have enough to make about 14 drivers total at the moment. But, don't hesistate to order, because you'll either just make it or you'll be next in line for when I do get parts.

Thanks!

 

[GoRdOn_B]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

i really like what i have heard about these.. im looking foreward to buying a couple

 

[sk8er4514]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

I went to work with one of your 803t range drivers last night in a MXDL case that I modified to use a Dorcy Jr heat sink (b/c i have a lot thanks to Dark Horse). I'm currently using two 3V CR123's ... I know this is only 6V and can tell that the laser isn't lasing very powerful at all. I'm going to go to the store today and get some 3.6V cr123's (maybe rechargeable, I'll see the prices for them) and should fix this low power lasing with 7.2V. hopefully it will work out well

I really liked the new drivers, was easy to solder the wires I had onto the driver. thanks for making these rkcstr

I'll probably be ordering more rkcstr drivers soon if i can find a way to hold the Dorcy heat sink in the MXDL in a better way. I am not going to pay $23 a heat sink to jayrob for some aluminum so modifying a smaller heatsink to fit into the MXDL is my only alternative... I cut up the MXDL reflector and flipped it around to point outwards and the heat sink fits in there pretty well, i need a better idea for it though.

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

yeah... 6V is WAY low for a higher powered violet. You may need upwards of 8V if you plan on going far over 100mA. I measured my diode I had at 150mA last night and it was running about 5.15V, meaning that 7.4V would be the MINIMUM, but considering slight other losses (resistance in wiring, variance in the regulator IC, maybe 30mV through the protection MOSFET, etc), it could need more like 7.5-7.6V. And, from what I've seen, my diode seems to be slightly higher efficiency than average, so others may run even higher voltage at the same current.

As for the heatsink... I have one of Jayrob's heatsinks and I think they're a GREAT deal! Very nicely made! They also do a very good job at cooling the Aixiz module. I have yet to buy the flashlight to complete the project, but I look forward to it.

I suppose if you're making/selling these, the added cost may not be worth it, though. Try looking on ebay (or elsewhere online) for aluminum rod stock that fits the inner diameter of your host then just find someone with a drill press and a bit slightly bigger 12mm or possibly 1/2" (12.7mm) and drill out a cavity to fit the module, then you can drill/tap a set screw hole to hold it in place (use thermal paste as well).

 

[sk8er4514]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

yeah... 6V is WAY low for a higher powered violet.  You may need upwards of 8V if you plan on going far over 100mA.  I measured my diode I had at 150mA last night and it was running about 5.15V, meaning that 7.4V would be the MINIMUM, but considering slight other losses (resistance in wiring, variance in the regulator IC, maybe 30mV through the protection MOSFET, etc), it could need more like 7.5-7.6V.  And, from what I've seen, my diode seems to be slightly higher efficiency than average, so others may run even higher voltage at the same current.

As for the heatsink... I have one of Jayrob's heatsinks and I think they're a GREAT deal!  Very nicely made!  They also do a very good job at cooling the Aixiz module.  I have yet to buy the flashlight to complete the project, but I look forward to it.  

I suppose if you're making/selling these, the added cost may not be worth it, though.  Try looking on ebay (or elsewhere online) for aluminum rod stock that fits the inner diameter of your host then just find someone with a drill press and a bit slightly bigger 12mm or possibly 1/2" (12.7mm) and drill out a cavity to fit the module, then you can drill/tap a set screw hole to hold it in place (use thermal paste as well).

hmm alright thanks for the help. I've been to walgreens & walmart and no where sells the 3.6V batteries anyways I'm not sure if it would work but I'm going to try to modify the MXDL to put a 9v battery in there. hah

maybe I'll put it all on the outside of it and just run wires inside.. i'll see how much room their is.

edit: finished! [link=http://www.laserpointerforums.com/forums/YaBB.pl?num=1216105989/0#0]check it out, lol[/link]

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

Well, I know you probably want them NOW, but you can get the 3.6V lithiums from DX and your 9v battery can suffice for now.

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

Domestic (within US) shipping costs are increased today. Only by $0.50 for the lowest cost, but I'm also going to be doing a tiered shipping cost since more drivers = more weight = higher postage, so for 1-3 shipping is $2.50, 4-10 is $3.00, 11 and up is $3.50. Priority mail has also increased to $5.50. The increase is due to a number of factors, but considering the small amount, I'm sure none of you really have a problem with it.

 

[ndrew2505]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

so what exactly are the input voltages for reds and br?

 

[daguin]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

so what exactly are the input voltages for reds and br?

The red diodes need 3V for themselves. The Rkcstr driver needs 2.3V. You need a minimum of 5.3V for the diode to lase. You should give it more than the minimum, but not overdo it. The excess voltage gets converted to heat.

The blu-ray diodes need 5V at low power outputs (below 100mW) Add the 2.3V for the driver and you need a minimum of 7.3V. However, as you drive the blu-ray to higher power output, the diode requires more voltage. If you push them as high as I do, they will need over 6V. Add the driver and you have a minimum requirement of 8.3V. I usually give my high powered blu-rays (with the Rkcstr driver) 11V to feed on. They will lase with lower voltage, but the output is lower as well.


Peace,
dave

 

[ndrew2505]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

so can the rckstr test load be used on any driver?

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

Thanks Dave!

The spec I give in my instructions and here are general guidelines... so you should always test things out before you go and put it all together. General rule of thumb, the theoretical drop out voltage, ie minimum voltage, as Dave explained, is 2.25V over the voltage the diode needs. Generally reds need around 3V, violet around 5V, but that depends on the operating current, as those values will go up/down, especially between models of diodes or even diode to diode. You can also add in margin of error of + 0.2V or so for the 2.25V, just in case. So, your typical burner diode might need around 5.5V or so, maybe more. A violet, low power, should be fine on about 7-7.5V, higher power violet may need upwards of 8V or more, depending on your operating current.

Also, your best bet is to shoot for an input voltage of not much more than 1-2V over the dropout voltage, as that will minimize the amount of heat it generates, and it will get HOT as you power over about 100mA, so make sure you're aware of how long you should keep it on before it gets very hot, which I'd suggest <1min. unless you can add some heatsinking. But, this isn't to say that these rules are absolute as I basically sell these things for people to experiment with, so go experiment!

so can the rckstr test load be used on any driver?

I don't see why not...

 

[rkcstr]

Re: Micro-Driver laser driver *NOW ADJUSTABLE*

Seems my orders seem to come in groups ;D I had nothing for a few days, then BOOM, 5 orders in two days.

Anyway, I'm working on getting them done, but I have some family visiting this weekend, so there won't be any going out today.

I'm also having some issues with my tin plating as my chemical plating solution crapped out on me, so its making it a pain in the butt to get the solder to stick. But, I don't think it should prevent me from getting the drivers finished and out on Monday.