DVD burner diode laser

• Sep 22, 2011

• #1

gulftown

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I have 2x3.6V LI-Ion batteries, housing, ddl driver, laser diode 16x, focus module ... all requirements for DYI laser. I just have 1 question with DDL circuit.
I use this
http://imageshack.us/photo/my-images/193/laserfromdvd.jpg
My question is: Are that 2 10ohm resistors really needed? Because I think, that the variable resistor can handle it itself? Or should be there one greater (10 ohm 1W for example). What do you think what is the best for driver. (I usually set variable resistor at 230-260mA).

 

Last edited: Sep 22, 2011

• Sep 22, 2011

• #2

chipdouglas

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if you plan on just leaving your pot set at the desired mA i think it could probably work. but the small pots are cheap and frequent adjustment will break them sending full current to kill your diode. thats what the resistors prevent.

michael.

 

• Sep 22, 2011

• #3

gulftown

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Also what's the best capacitor for this circuit? 'cause some people here wrote that it has to be 47μF ...

 

• Sep 22, 2011

• #4

chipdouglas

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well why do think they wrote that???

 

• Sep 23, 2011

• #5

gulftown

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I don't know, I think that capacitor value is not so important. So should I use 47uF capacitor and 10 ohm resistor for best results?

 

• Sep 23, 2011

• #6

midias

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If you are running 250ma and 5 ohms on the pot you got about 0.3W make sure the pot is rated for that and it will work out.

 

• Sep 25, 2011

• #7

gulftown

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So i shouldn't use any resitstor, only pot set on 5Ω (pot 100Ω 0.5W), or should I use one 2Ω resistor (0.5-1W) and pot set on 3Ω? And with capacitors, I have tons of 'em I can find any rate. Which would be the best?

 

Last edited: Sep 25, 2011