Buildind my first DDL Driver

[jaycey]

1N4003 will be fine, they are slightly different from a 1N4001 but it wont make any difference in this application.
3.3ohm 1/2 watt resistor is spot on, 1/2 watt = 500mah you are going to put 378mah through it so it shouldnt get too hot.

Remember to ALWAYS short your capacitor before connecting your laser diode.

Your getting there!

P.S. be carefull with the open can red, they are a sensitive/fragile little diode. Watch out for ESD and too much heat when harvesting and soldering the diode.

Guys you are totally awesome!! I love this forum :thanks:
So i decided to go with the driver without the pot since i have a good feeling i would turn the pot to high and blow my diode..
I went out today to look for the parts and these are all i can find..
LM317
1N4003......I know its suppose to be 1N4001 but the girl there said that its the same, can anyone tell me if this is true?
3.3 1/2watt resistor........Whats the purpose of 1 Watt or half Watt?
Im using an open can red laser, so with 3.3 resistor i shoud get about 378mA output, that should be good right? please give me any advice that you all think i might need, and thanks again..

 

[Eudaimonium]

Guys you are totally awesome!! I love this forum :thanks:
So i decided to go with the driver without the pot since i have a good feeling i would turn the pot to high and blow my diode..
I went out today to look for the parts and these are all i can find..
LM317
1N4003......I know its suppose to be 1N4001 but the girl there said that its the same, can anyone tell me if this is true?
3.3 1/2watt resistor........Whats the purpose of 1 Watt or half Watt?
Im using an open can red laser, so with 3.3 resistor i shoud get about 378mA output, that should be good right? please give me any advice that you all think i might need, and thanks again..

I'm glad you are enjoying your stay here.

Anyhow, difference between 1n400x series is the total voltage they can take.
1n4001 can take up to 50V IIRC,
and 1n4007 can take 1000V.

Since you are talking about 3V here, apsolutely any will do.

3.3 ohms fixed resistor is an excellent choice.
Wattage of the resistor determines the maximum amunt of electrical energy flowing through it.
Let's say you have 1W resistor, and you have 10V circuit. You must not push any higher than 100mA though it.
Or if you have 1V, you do not push above 1A of current though it.

Lets not show someone how to "run before they can walk"

My driver was large to illustrate to people who have not put one together before how it "can" be done.

I dont think someone new to electronics is going to grab a handfull of SMD components and put together one of those.

Nice little driver btw

Yeah, good point there

I was just trying to show, although the tht setup is a good starter driver, you can get a very tiny drivers that will fit in good nice hosts with exact same componens, only SMD package. Not neccessary to buy expensive drivers in order to have yuor laser built into a flashlight or anything.

Oh and thanks !

 

[Last One Left]

Thnaks alot guys!! i would build it up in the morning, i think im good for the while..you all helped me alot and i do have some knowledge of soldering so with these pcb components i should be good..i would be careful with the open can diode..there is a chance that i already may have damaged it when i tried it out using the driver my axis 5mW 650nm came with, but hopefully its still good..
Apart from the open can diode, i also have a normal sealed diode that i got from an 8x DVD burner, can i use the same driver (3.3 resistor) with it? thanks again..

 

[Eudaimonium]

Thnaks alot guys!! i would build it up in the morning, i think im good for the while..you all helped me alot and i do have some knowledge of soldering so with these pcb components i should be good..i would be careful with the open can diode..there is a chance that i already may have damaged it when i tried it out using the driver my axis 5mW 650nm came with, but hopefully its still good..
Apart from the open can diode, i also have a normal sealed diode that i got from an 8x DVD burner, can i use the same driver (3.3 resistor) with it? thanks again..

Open can diode is most likely not fried as the stock driver is designed to provide around 30mA if I am not mistaking.
That is (also IIRC) below lasing threshlond current, so no damage done.

8x burner diode ... depends on the type of the diode.
If it is SCC (short closed can), then no, you not want to go above 300mA on it.
If it is any kind of long die diode, yup, 3.3 ohm resistor for the win and laser

 

[Last One Left]

Ok guys well i put together my driver today, and i think everything was placed in correctly, but im having a problem..my open can diode lights up very dim, so im thinking that its broken..i thought im might be since i wasnt as gentle with it when i first took it out (i didnt know)..
I do have a question..is it possible that the heat rom the solder iron could have damage the driver parts? thanks..

 

[Eudaimonium]

Ok guys well i put together my driver today, and i think everything was placed in correctly, but im having a problem..my open can diode lights up very dim, so im thinking that its broken..i thought im might be since i wasnt as gentle with it when i first took it out (i didnt know)..
I do have a question..is it possible that the heat rom the solder iron could have damage the driver parts? thanks..

To the driver parts, no , highly unlikely.
But appears your diode has gone to LED land now

Have you measured the current draw ? Masure it between the driver and the battery.
What kind of battery are you using actually?

Can you post some pictures of your entire setup?

 

[Last One Left]

Thanks for the reply...
I have not measure the current draw, can you explain what you mean by that..
Also im not using batteries, im using a 3v 500ma adapter..would this be a problem? Thanks..

 

[harryd]

just a quick question plz regarding the equation above. my laser diode says that the operating current is 35mA and max 50mA.
1.25/50ma= 25 ohm, 1.25 /35ma= around 36 ohm

does this mean that the max of the laser diode is when pot is at 20 ohms ( since there is a 5ohm fixed from the 2x 10 ohm )

and the min , lets say the min current is 25 ma, is 45 ohm at the pot ( since there is 5 fixed from the 2x 10ohm ).

so if i change the value of the pot starting from 45 ohm and gradually decrease the value to 25, the output power will increase?

plz someone help

thanks in advance