Driver mA to mW ?

Hey all,

I remember seeing somewhere, someone or maybe a lot of people had a type of estimate for setting their driver "flex drive" or buying specific drivers to power specific mW diodes. Someone had an estimate for how many mA you want to power a certain amount of mW. Sorry, even a link will work if this is explained somewhere, sorry for the redundancy.

I'm just trying to understand, or maybe is there certain mA for certain mW for specific wavelength. For example, we all know that the driver attached is known to work well for 1W of 445 , but why do I find on the olike website, that it says its good for 200mW of 405?


Or if anyone just wants to try to explain how they decide what driver they are going to use when they are deciding to build. Thanks!

Not all diodes are the same. The ratio of mA: mW is dependent on their efficiency. Just because a driver says 1W does not mean you'll get 1W. It's really just marketing. 1W of 445nm is usually gained by supplying the diode a bit more or less than a full Ampere. Again it depends on efficiency.
You can look up a power graph of a diode to get a sense of their input current to the output wattage.
Flexdrives were just popular thus used a lot. Now the source for them is pretty elusive.
Also, it says 1W off 445nm and 200mW of 405nm, but it isn't just a simple diode replacement. You need to alter the current. 1A of current will kill a 405nm diode VERY QUICKLY.
Personally I choose a driver based on the host. If its a single cell host, I'll spring the extra cash for a boost driver. Luckily now boost drivers have decreased in price.
However if it's a big >2 cell host, I usually build a linear driver.
For lab type builds I always use a linear driver because I use wall supplies.

Thanks, that helps a lot. If anyone else feels like sharing their opinion, I'd love to listen.

Judging by the type of driver you've shown, you are most likely planning on making a 1W 445nm laser. The different diodes for 445nm also make a huge difference in quality and efficiency. What diode are you planning on using? Assuming you are actually going to use this information

I have already built a 1watt 445 with that driver, yes. But I guess what I wanted to learn from this post is more information about drivers, and how I determine the differences between the same driver and different wavelength laser diodes.

For example, I know that, that driver was best for a 1watt 445, but I really don't understand the amperage behind it. I just bought that driver, because I knew I didn't have to do anything to it, but install it, and supply it with a 3.5-4volt source and it would be compatible. Yes that makes me sound stupid, but hey my laser works great...soo...that's why I made this post. I read the other stickies pertaining to drivers, and so this post was just to specify what I was looking for, due to the sticky being explained in such a way for beyond my knowledge on the topic.

Just wanted other peoples feedback on how they choose drivers, etc. Fretwreckers post was very relevant to what I was asking, just curious if anyone else had relative feedback.

And in reference to actually using this information, yeah I'd love to use it for building many lasers in the future.

Well different wavelength lasers diodes use different material for the gain medium these different gain mediums have different vf and depending on the manufacture process different current thresholds this gives us the violets at 600mw and the blues at 2 watts sect
Now on the driver from u can get something like the Ben boost current set and aslomg as the vf is higher than the source voltage your fine you do not have to set the voltage for diodes drivers automaticly do that for you you do however have to set the Amps

Yeah, ok, sounds good!

How do you respond to something like this:

I had a "30mW laser" took the driver out of it to power a "80-100mW" laser. The new laser definitely looks way brighter, but is it really? Same driver, same voltage, means it is pushing the diode the same amount? Check out the pics of the laser I'm speaking of.

http://laserpointerforums.com/f48/first-build-100mw-greenie-73253.html#post1056326

Was the driver the laser came out of the same wavelength (color) since IR diodes are used to drive green lasers in a Dpss process rather than doing it direct diode

Oh yeah, I forgot to say that, yeah they were both green. So yeah both DPSS.

As a side not, doesn't those pics look higher power than 30mW?

dlipford370 said:

Yeah, ok, sounds good!

How do you respond to something like this:

I had a "30mW laser" took the driver out of it to power a "80-100mW" laser. The new laser definitely looks way brighter, but is it really? Same driver, same voltage, means it is pushing the diode the same amount? Check out the pics of the laser I'm speaking of.

http://laserpointerforums.com/f48/first-build-100mw-greenie-73253.html#post1056326

Click to expand...

The higher power a diode is rated for, the more output it has at a lower current sometimes, because they are more effecient. So if your 30mW laser needed that driver's current to push it to 30mW, then that same current could (in some cases) give you a higher mW output than before, due to the stronger diodes higher efficiency. Now, that said, it is also probably not 80mW-100mW output if the diode is rated for 100mW and your powering it with a 30mW laser's driver. It is probably putting out about 40mW-50mW. If there is a potentiometer (looks like a screw) on your driver, try turning the resistance on it down, letting more current flow to the diode. Just a word of warning though, do NOT overturn the pot, or you will fry your diode.

Or if you want guaranteed range on the linear end a groove drive or if you fixed currents go with a ghost dive just getting that out there

Personally I would not recommend that driver. I don't believe it is a constant current driver. I am assuming that is how it is for both a blue ray and a 445 with no pot adjustments. With higher voltage forward it drops current and if that is correct then it is dangerous if the battery has a voltage spike on start up especially with a 405 diode. I have also had many customers have problems with them. I would just grab a ben boost.:beer:

This driver.

DTR said:

Personally I would not recommend that driver. I don't believe it is a constant current driver. I am assuming that is how it is for both a blue ray and a 445 with no pot adjustments. With higher voltage forward it drops current and if that is correct then it is dangerous if the battery has a voltage spike on start up especially with a 405 diode. I have also had many customers have problems with them. I would just grab a ben boost.:beer:

Click to expand...

Groove or Ghost?

Ghostchrome said:

Groove or Ghost?

Click to expand...

Not sure what you mean. I though he was talking about boost drivers?

I meant the O-Like drier he pictured in the OP if that is what you meant.

^^ Oh, whoops! I thought you were talking about mattco2's post above yours. (post #11)

ok i might want to add this linears are only effective on builds with 2 batteries or more
the voltage needed for a linear can be calculated by this formula

Vr=VFd+VDd
were Vr is the needed voltage VFd is the voltage forward of the diode and VDd is the dropout voltage of the linear driver
i believe that dtr was referring to the crap driver he pulled out of a china pointer