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3 variable power lasers






Laser don't have a mA output... the drivers do...
Laser have mW output...

Do a little research on the Forum...
Use the [Search] button to find drivers and driver circuits...

BYW.... welcome to the Forum...

Jerry
 
lasersbee said:
Laser don't have a mA output... the drivers do...
Laser have mW output...

Do a little research on the Forum...
Use the [Search] button to find drivers and driver circuits...

BYW.... welcome to the Forum...

Jerry
Click to expand...

Aw come on, you know that that's what he meant.

@OP: You would want to install potentiometers between the drivers and the diodes.
 
Yeah... but that's not what he said....
Being clear and precise is not a Negative....

Aw come on.... keep spoon feeding the new guys...

Ever heard this one...

"Give a man a fish and you feed him for a day....
Teach a man to fish and you feed him for a lifetime"....


Jerry
 
Grix said:
Aw come on, you know that that's what he meant.

@OP: You would want to install potentiometers between the drivers and the diodes.
Click to expand...


No, you do not want to do this. The driver will try to maintain current by increasing voltage. You will only be pushing the driver to the dropout point. You want to install a potentiometer in the driver circuit, in series with the main setting pot. That way when the pot becomes a short at zero resistance you will only get your maximum set current. The system is very fail-safe but is only for LM317 type drivers.
 
MarioMaster said:
No, you do not want to do this. The driver will try to maintain current by increasing voltage. You will only be pushing the driver to the dropout point. You want to install a potentiometer in the driver circuit, in series with the main setting pot. That way when the pot becomes a short at zero resistance you will only get your maximum set current. The system is very fail-safe but is only for LM317 type drivers.
Click to expand...

K, disregard my last post. I guess I learned something today too.
 
Sorry Jerry but there's not much info on this. OP, you could use a 555 to make a PWM, use google to learn how.
 
I have been wondering for a long time about the usage of a DS1669 digital potentiometer chip to control the LM317K, and wondering if it could be done to control electronically the power of the individual lasers of a RGB laser...

The red and blue shouldn't be too challenging, integrating the 8-pin dip, who needs no additional parts to run to a homemade LM317K-based PS. For a green module, I imagine carefully desoldering the pot on the driver board and replacing it with a combination DS1669 and limiting resistor on a tiny daughterboard should be possible...

http://datasheets.maxim-ic.com/en/ds/DS1669.pdf

Now imagine digitally controlling the power of each laser via a USB interface controller... but I'm getting over my head a bit, I'm sure some members with more technical saavy than I would think this might be a cool idea to make a multicolor-programmable laser spiro or something of that sort, and have the knowledge to design such a device... just a thought...

Robert
 
roddenberry said:
I have been wondering for a long time about the usage of a DS1669 digital potentiometer chip to control the LM317K, and wondering if it could be done to control electronically the power of the individual lasers of a RGB laser...

The red and blue shouldn't be too challenging, integrating the 8-pin dip, who needs no additional parts to run to a homemade LM317K-based PS. For a green module, I imagine carefully desoldering the pot on the driver board and replacing it with a combination DS1669 and limiting resistor on a tiny daughterboard should be possible...

http://datasheets.maxim-ic.com/en/ds/DS1669.pdf

Now imagine digitally controlling the power of each laser via a USB interface controller... but I'm getting over my head a bit, I'm sure some members with more technical saavy than I would think this might be a cool idea to make a multicolor-programmable laser spiro or something of that sort, and have the knowledge to design such a device... just a thought...

Robert
Click to expand...


I've been considering this too. Need to look into the idea more. There are other ways to analogue modulate lasers, but I don't know how this is done very well, yet. As for the green driver, just use an LM317 for that too. I'm going to start looking into this idea soon ;)

Regards,

Adam
 
nikokapo said:
Sorry Jerry but there's not much info on this. OP, you could use a 555 to make a PWM, use google to learn how.
Click to expand...

Hey niko... any DDL driver can be made adjustable/variable....
The guy in the YouTube video uses a pot to control the intensity (mA)
of the LD... I would bet he is using a DDL driver driver.
And the DDL circuits are all over the Forum..
If the question was... "is there a way of making the DDL circuit adjustable"
then I would probably have responded in a more positive tone..

Gee.. you could even do an updated/improved KipKay and drive the LDs
directly using a Voltage Regulated Power supply through fixed Max Current
limiting resistors and a pots.

I will admit... you do need a smigin' of electronic basics.


Jerry
 
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roddenberry said:
I have been wondering for a long time about the usage of a DS1669 digital potentiometer chip to control the LM317K, and wondering if it could be done to control electronically the power of the individual lasers of a RGB laser...

The red and blue shouldn't be too challenging, integrating the 8-pin dip, who needs no additional parts to run to a homemade LM317K-based PS. For a green module, I imagine carefully desoldering the pot on the driver board and replacing it with a combination DS1669 and limiting resistor on a tiny daughterboard should be possible...

http://datasheets.maxim-ic.com/en/ds/DS1669.pdf

Now imagine digitally controlling the power of each laser via a USB interface controller... but I'm getting over my head a bit, I'm sure some members with more technical saavy than I would think this might be a cool idea to make a multicolor-programmable laser spiro or something of that sort, and have the knowledge to design such a device... just a thought...

Robert
Click to expand...
I've worked with these... and the max current of the one you
linked to is only 1mA.
Could be used to vary/control a higher current driver system.
What I like about that one is that it remembers the pot wiper
position even if power is removed... and you can control it with
only 2 push buttons..


Jerry
 
lasersbee said:
I will admit... you do need a smigin' of electronic basics.
Click to expand...


Are you being serious?



He wanted to adjust the power while the diodes were lasing, he didn't ask how to build a current regulated driver (info about that is everywhere) so I suggested a PWM circuit which he would've to look up on Google. I don't see where I'm making a mistake here.
 
Never said you were making a mistake...:evil:

Hey niko... 2 more posts....


Jerry
 
lasersbee said:
Never said you were making a mistake...:evil:

Hey niko... 2 more posts....


Jerry
Click to expand...

I know, now only ONE :p

Though I still don't get why the "electronic smidgin'" is needed.






EDIT:


v Haha I'll have to make a big deal out of my 4k :p, sorry dude I thought you were talking about me and not the OP.
 
Last edited:
I was just saying that for the OP to be able to build any circuit I mentioned
that at least a "small" amount of basic electronics knowledge would be required..

OK... reply to this and you'll have hit it...:wave:

Jerry
 
Niko in honor of your 4K post, I am raising my glass of Guiness to you my friend!

@ laserbee: Yeah I know, but I don't think the "adjust" part of the LM317K in such a circuit dissipates much power (usually a 1/4 or 1/8w resistor will suffice), but you're right, maybe there are chips similar to the DS1669 that can handle a bit more power. The original usage of these chips was in hi-end power amps to control the volume and avoid the scratchy dirty pot sound because of the "debouncing" circuitry inside.

Robert
 
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