Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

What are the differences between driver units?

Joined
Dec 31, 2008
Messages
34
Points
0
First off, can anybody just plug this website into my brain and dump it in like the Matrix?  ;)

But seriously, I am currently intending to build a Daedal driver for use with a BR LD.  Is this a reasonable idea, or do I NEED a rckstr or flexdrive?  I'm not afraid of building my own stuff, but I don't know if the rckstr/flexdrive units have something significant that the DIY one doesn't.  Thanks in advance!
 





Joined
Feb 18, 2008
Messages
733
Points
18
The DDL driver should work on most diodes if not all of them (as long as the amps aren't to high). The DDL driver needs >8.2v for BR diodes (usually). The rckstr driver also needs >8.2
volts but is much smaller.

The flexdrive generates little heat and only needs 2.5-5.5v's (can't go above that but a silicon diode will let you use 6.5V.

--hydro15
 
Joined
Dec 31, 2008
Messages
34
Points
0
Thanks for the quick reply and concise description of the differences. For my current application, heat dissipation shouldn't be an issue and it is mains powered, so lots of voltage can be made available. So looks like I will forge ahead with the DDL driver.
 

kendon

0
Joined
Jan 12, 2009
Messages
154
Points
0
if you excuse to pull this up again, but i was just wondering about the exact same thing. i just threw an order of parts for five ddl's together, summed up to 4 euro. that 0.80 euro each, ~1$. so why would i want to spend up to 20$ for a prebuild circuit?
i could think of:

- size
- lazyness
- lack of competence to build it

are there more good reasons?

and also, is there any change necessary in the design of ddl's circuit for different diodes (green/br/blue etc.) or is it as simple as using different input voltages?
 
Joined
Jan 6, 2008
Messages
68
Points
8
kendon said:
are there more good reasons?

Yes, the flexdrive works with much lower input voltages. if you need to use a power source with a lower voltage, the flexdrive can be a godsend.

kendon said:
and also, is there any change necessary in the design of ddl's circuit for different diodes (green/br/blue etc.) or is it as simple as using different input voltages?

You don't necessarily need to change the voltages, it just need to be high enough so all the parts get enough volts. A BR diode has a higher voltage drop than a red diode, and that is why it needs a higher voltage.

What should be changed however is the resistor in series with the potentiometer. This resistor determines the maximum output current of the driver. the equation you want to use to calculate the value the resistor should be is 1.25/A = R . e.g. 1.25/.04A = 31.25 ohms (.04A = 40mA, which is a good max for the ps3 br, maybe a little bit too low). It would be a good idea to look up the recommended max current for the specific diode you use, it varies specific to the model. closed cans generally have lower max currents than open cans, short die higher than long die. A thread with info about max currents is http://www.laserpointerforums.com/forums/YaBB.pl?num=1217284580/0#0
 
Joined
Oct 26, 2007
Messages
5,438
Points
83
Look at what each driver type offers and see what fits your needs. If you need to drive your laser via low-voltage power sources, you'll probably want a Flex drive. If space is a concern the Flexdrive or Rckstr driver will be good. If neither matters, go with the DDL circuit, as it'll be cheaper.

You should read up on how they work and what they're best used for before buying. Some drivers use regulators that have a higher voltage requirement than others, others require a voltage below a certain amount or you'll burn out the driver (flex). I'd also invest in a decent multimeter so you can measure the output, etc.
 

kendon

0
Joined
Jan 12, 2009
Messages
154
Points
0
awesome, thx a lot.

i already figured out the function of the resistor(s), and for the moment i don't care about size or power supply, since these are my first experiences "playing" with lasers.

but this is very valuable information when it comes down to size or power, so thanks again.

keep it coming if you have more regards on the circuit!
 




Top