Laser pointer discussion. Read/write reviews of laser pointers and laser pointer companies. Learn about all types of laser pointers and lasers





Welcome to Laser Pointer Forums! If you are looking for a laser pointer or want to compare different laser pointer companies, you may want to check out the LPF Laser Pointer Company Database. The link will open in a new window for your convenience.








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes
Laser Technology Laser Pointer Parts Lasers by Wavelength
Top 10 Laser Pointer Companies Laser Pointer Company Database Visible Beam Laser Pointers


One laser store meets all your needs

























Go Back   Laser Pointer Forums - Discuss Laser Pointers > Lasers > Experiments & Modifications



LPF List of Laser Pointer Companies (link opens new window)



Closed Thread
 
LinkBack Thread Tools Display Modes
Old 07-30-2007, 12:18 AM #17
Class 1M Laser
 
Join Date: Jun 2007
Posts: 100
Rep Power: 11
yuip is on a distinguished road
yuip yuip is offline
Class 1M Laser
 
Join Date: Jun 2007
Posts: 100
Rep Power: 11
yuip is on a distinguished road
Default Re: DIY Homemade laser diode driver

Okay, I have a few questions. :P

In the circuit diagram, the resistor is 4 ohms. You used a 10 ohm resistor in your circuit because you had it close by, but does it make any difference. I am guessing that it doesn't because you included a 4 ohm resistor in the diagram, linked to a 15 ohm resistor at DigiKey, and a 15 ohm resistor isn't included in the RadioShack pack.

So does the value of the resistor matter much?

Pardon my ignorance, and thanks again!


yuip is offline  







LPF List of Laser Pointer Companies (link opens new window)







Old 07-30-2007, 12:28 AM #18
Class 3R Laser
 
Join Date: Oct 2006
Posts: 2,032
Rep Power: 31
pseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud of
pseudonomen137 pseudonomen137 is offline
Class 3R Laser
 
Join Date: Oct 2006
Posts: 2,032
Rep Power: 31
pseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud of
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by Daedal
Connect the laser diode and make sure the capacitor is SOLDERED to the laser diode pins, be it through wires or directly on the back of the laser diode. If the laser diode happens to disconnect from the capacitor and then reconnect while the capacitor is charged, then that’ll be worse than the spike from the battery itself! It will literally dissipate all the charge almost instantaneously to the laser diode and fry it because it has very little internal resistance…
Minor detail, but can you please explain why this is? I would think that when the cap is in the circuit it would only charge up to the voltage that's already on the diode. Then even if the cap were then directly hooked up to the diode alone, wouldn't it still apply, at most, the same voltage to the diode and thus not kill it? Or am I just completely confused here :-/
pseudonomen137 is offline  
Old 07-30-2007, 12:50 AM #19
Class 1M Laser
 
Join Date: Jun 2007
Posts: 100
Rep Power: 11
yuip is on a distinguished road
yuip yuip is offline
Class 1M Laser
 
Join Date: Jun 2007
Posts: 100
Rep Power: 11
yuip is on a distinguished road
Default Re: DIY Homemade laser diode driver

From what I've been told the main reason for the capacitor in very simple LD circuits (just a cap and resistor) is too smooth out in voltage spikes and give the diode a "soft start".

You are right, it seems that the cap would only charge to the voltage on the diode. I think what Daedal is saying is that you can't just connect 2.8-3.0 volts at 250-300mA directly to the diode, since many of the DVD burner red diodes have a threshold of only 100mA according to the spec sheets I've seen.

The way I understand it is that the capacitor slowly charges and slowly outputs more and more current, so that the laser diode doesn't die a quick death by the high current. If the LD became disconnected from the cap after running for a little bit, and was suddenly reconnected, the normal current you want to run the diode at would kill it.


Wow, I just realized I was talking in circles. :-[

Then again, I have no idea what I'm talking about, and probably am wrong.
yuip is offline  
Old 07-30-2007, 12:52 AM #20
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

I found a seller on e-bay that has some of the SMD's we would need if we wanted to make the circuit smaller. The problem is what would we mount the SMD's to? I think I am going to skip trying this. The parts are extremely small and a pain to work with. I have in the past, but building a circuit from scratch would be very difficult...I would think. I suppose it could be done by super gluing the parts to a small board, then wire them up with small wire. But we would have the problem of heat sinking the SMD version of the LM317.

Gazoo is offline  
Old 07-30-2007, 12:54 AM #21
Hemlock_Mike's Avatar
Class 4 Laser
 
Join Date: Jan 2007
Location: North Iowa
Posts: 6,184
Rep Power: 4058
Hemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond repute
Hemlock_Mike Hemlock_Mike is offline
Class 4 Laser
Hemlock_Mike's Avatar
 
Join Date: Jan 2007
Location: North Iowa
Posts: 6,184
Rep Power: 4058
Hemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

The LM317 in this circuit is a current source. If the load (LD) disconnects, the Cap will charge to about 6 volts. Reconnect to the LD and you might have an LED The cap at 6 volts might blow the LD. (It's happened to me )

Mike
__________________
It's a dog's life
Hemlock_Mike is offline  
Old 07-30-2007, 12:59 AM #22
Class 3R Laser
 
Join Date: Oct 2006
Posts: 2,032
Rep Power: 31
pseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud of
pseudonomen137 pseudonomen137 is offline
Class 3R Laser
 
Join Date: Oct 2006
Posts: 2,032
Rep Power: 31
pseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud ofpseudonomen137 has much to be proud of
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by Hemlock Mike
The LM317 in this circuit is a current source. If the load (LD) disconnects, the Cap will charge to about 6 volts. Reconnect to the LD and you might have an LED The cap at 6 volts might blow the LD. (It's happened to me )

Mike
Oh, so the problem is not with the charged cap temporarily disconnecting, but with the diode itself disconnecting?
pseudonomen137 is offline  
Old 07-30-2007, 01:25 AM #23
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Daedal Daedal is offline
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by Gazoo
My suggestion would be to change that statement to something like as follows:

"How?
To regulate the voltage we will use a voltage regulator and set it up in voltage regulation mode and limit the supplied voltage. And we will use a capacitor to ensure no voltage spikes reach the diode."

Again you have done an outstanding job with your write up and in fact I plan to try it myself. I am looking forward to whatever SMD parts you can find. We do know there is a smaller variation of the LMT317 that can handle up to 500ma's.

BTW, do you know how warm the LM317 gets in your circuit? I mean does it feel hot?
Gazoo, thank you very much for your suggestion, although we are NOT using the LM317 to regulate the voltage. In this circuit I am using the capacitor to dull away the spikes from the battery and the silicon diode to provide polarity protection.

As about the LM317T, it doesn't get anywhere near hot at that supply. A smaller one would definitely start feeling a little warm, but this one feels to be at room temperature even after about 10-15 minutes..

Thank you;
DDL
__________________
____________________________________________
Daedal Lasers... NEW LOWER PRICES... LPF Coupon = LPF10OFF
________________________________
CLICK ME -- LASORB is now available for immediate purchase
________________________________
Daedal is offline  
Old 07-30-2007, 01:32 AM #24
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Daedal Daedal is offline
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by yuip
Okay, I have a few questions. :P

In the circuit diagram, the resistor is 4 ohms. You used a 10 ohm resistor in your circuit because you had it close by, but does it make any difference. I am guessing that it doesn't because you included a 4 ohm resistor in the diagram, linked to a 15 ohm resistor at DigiKey, and a 15 ohm resistor isn't included in the RadioShack pack.

So does the value of the resistor matter much?

Pardon my ignorance, and thanks again!
I am very sorry about yet another blunder int he post... I will fix it immediately. Please understand that I did this really late at night... :-[

As about the resistor, if you use a 4 ohm resistor, then you limit the maximum voltage to 312.5 mA. If you use a 10 ohm the maximum that will be passed through will be 125 mA. Therefore, yes it makes a huge difference. I will fix the links momentarily.

Thank you;
DDL
__________________
____________________________________________
Daedal Lasers... NEW LOWER PRICES... LPF Coupon = LPF10OFF
________________________________
CLICK ME -- LASORB is now available for immediate purchase
________________________________
Daedal is offline  
Old 07-30-2007, 01:40 AM #25
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Daedal Daedal is offline
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by pseudonomen137
[quote author=Daedal link=1185701612/0#1 date=1185701644]
Connect the laser diode and make sure the capacitor is SOLDERED to the laser diode pins, be it through wires or directly on the back of the laser diode. If the laser diode happens to disconnect from the capacitor and then reconnect while the capacitor is charged, then that’ll be worse than the spike from the battery itself! It will literally dissipate all the charge almost instantaneously to the laser diode and fry it because it has very little internal resistance…
Minor detail, but can you please explain why this is? I would think that when the cap is in the circuit it would only charge up to the voltage that's already on the diode. Then even if the cap were then directly hooked up to the diode alone, wouldn't it still apply, at most, the same voltage to the diode and thus not kill it? Or am I just completely confused here :-/
[/quote]

The reason for the nice spike from the capacitor in such a case if because basically the capacitor is charged up like a second battery. This second battery has very little to no internal resistance and is not regulated by the LM317, in fact it is directly wired to the LD... thus when the LD works as a discharge venue for the capacitor, the electrons are eager to go through the tiny wire and will instantly fry it. In a case like this the LD won't turn into an LED, the hair-thin wire inside the diode will overheat and snap like a fuse wire. The internals of the LD would all be fine, but it would be disconnected...

I am not sure if this explains it any further Pseudo. Sorry if not, and please feel free to ask more if you need;
DDL
__________________
____________________________________________
Daedal Lasers... NEW LOWER PRICES... LPF Coupon = LPF10OFF
________________________________
CLICK ME -- LASORB is now available for immediate purchase
________________________________
Daedal is offline  
Old 07-30-2007, 01:48 AM #26
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Daedal Daedal is offline
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by pseudonomen137
[quote author=Hemlock Mike link=1185701612/15#20 date=1185756896]The LM317 in this circuit is a current source. If the load (LD) disconnects, the Cap will charge to about 6 volts. Reconnect to the LD and you might have an LED The cap at 6 volts might blow the LD. (It's happened to me )

Mike
Oh, so the problem is not with the charged cap temporarily disconnecting, but with the diode itself disconnecting?
[/quote]

Mike, thank you very much! This is exactly what I was trying to say.

Pseudo, the capacitor is the danger here. If the LD is disconnected form the Cap and then a second later reconnected, you have a fatal situation. If the capacitor is soldered to the LD permanently, then you could disconnect and reconnect the pair as much as you want, and nothing would endanger the LD. At least that is how it works in theory...

--DDL
__________________
____________________________________________
Daedal Lasers... NEW LOWER PRICES... LPF Coupon = LPF10OFF
________________________________
CLICK ME -- LASORB is now available for immediate purchase
________________________________
Daedal is offline  
Old 07-30-2007, 01:52 AM #27
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

Daedal, I am trying to understand why you need the diode. If I am understanding the circuit, the diode effectively is converting the 6 volt battery to a 5.5 volt battery. This is the same thing as adding a half volt to the dropout voltage. I guess what I am asking is wouldn't a resistor with a higher value accomplish the same thing?
Gazoo is offline  
Old 07-30-2007, 02:00 AM #28
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Daedal Daedal is offline
Class 3R Laser
 
Join Date: May 2007
Posts: 2,277
Rep Power: 175
Daedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond reputeDaedal has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

I have updated the link for the resistor to a 3.9 Ohm resistor offered at Digikey. This would limit the max current supply to around 320mA.

Please all remember that you can ADD resistors as follows:

----====----====----
R1 R2

This is the same as one resistor equal to R1 + R2. Therefore if you wanted exactly 4 Ohms you could put 4 resistors in series.

Also, you can reduce resistors as follows:

--|--====--|-- <-- R1
--|--====--|-- <-- R2

This adds up as follows:

1/R = 1/R1 + 1/R2 and can keep adding up as many as you want. Thus two 10-ohm resistors in parallel are the same as one 5-ohm resistor. The benefit is that in this case the ratings would add up, merging these 2 1/4 watt resistors into one 1/2 watt resistor

GL;
DDL
__________________
____________________________________________
Daedal Lasers... NEW LOWER PRICES... LPF Coupon = LPF10OFF
________________________________
CLICK ME -- LASORB is now available for immediate purchase
________________________________
Daedal is offline  
Old 07-30-2007, 02:05 AM #29
Class 1M Laser
 
Join Date: Jun 2007
Posts: 100
Rep Power: 11
yuip is on a distinguished road
yuip yuip is offline
Class 1M Laser
 
Join Date: Jun 2007
Posts: 100
Rep Power: 11
yuip is on a distinguished road
Default Re: DIY Homemade laser diode driver

Quote:
Originally Posted by Daedal
[quote author=pseudonomen137 link=1185701612/15#21 date=1185757164][quote author=Hemlock Mike link=1185701612/15#20 date=1185756896]The LM317 in this circuit is a current source. *If the load (LD) disconnects, the Cap will charge to about 6 volts. *Reconnect to the LD and you might have an LED The cap at 6 volts might blow the LD. *(It's happened to me )

Mike
Oh, so the problem is not with the charged cap temporarily disconnecting, but with the diode itself disconnecting?
[/quote]

Mike, thank you very much! This is exactly what I was trying to say.

Pseudo, the capacitor is the danger here. If the LD is disconnected form the Cap and then a second later reconnected, you have a fatal situation. If the capacitor is soldered to the LD permanently, then you could disconnect and reconnect the pair as much as you want, and nothing would endanger the LD. At least that is how it works in theory...

--DDL[/quote]

Oh okay, so my explanation was pretty flawed. ;D

Eh, thanks for the clarification about the resistor value as well. No need to apologize. I can't thank you enough for taking the time to write up this guide in the first place. I think I'll try to make one of my boards with a removable resistor so I can tinker around with driving a diode past 500mA with pretty extreme cooling.
yuip is offline  
Old 07-30-2007, 02:37 AM #30
Hemlock_Mike's Avatar
Class 4 Laser
 
Join Date: Jan 2007
Location: North Iowa
Posts: 6,184
Rep Power: 4058
Hemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond repute
Hemlock_Mike Hemlock_Mike is offline
Class 4 Laser
Hemlock_Mike's Avatar
 
Join Date: Jan 2007
Location: North Iowa
Posts: 6,184
Rep Power: 4058
Hemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond reputeHemlock_Mike has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

DDL is doing his best to explain a really basic circuit which has been around for years. *He's telling you that the 4 ohm resistor sets the "MAXIMUM" current from the LM317 and the 10 ohm is the variable part which reduces the current to a lower level. *HINT: Start low.
NOW: *He is working with a specific LD (diode) which has its own parameters so YMMV with what you connect this to. *Each diode has its own forward voltage drop and the "effective" ohms (V/I) is not linear. *You have to be careful at the top end.
A bunch of us, SenKat, DDL, Gazoo and myself among many others, have found this out the hard way * * *You will be in good company if you cook an LD yourself *

Mike
__________________
It's a dog's life
Hemlock_Mike is offline  
Old 07-30-2007, 02:47 AM #31
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Homemade laser diode driver

Tell me about it. I have cooked at least six so far ;D Your advice is very good.
Gazoo is offline  
Old 07-30-2007, 02:47 AM #32
SenKat
Guest
 
Posts: n/a
SenKat
Guest
 
Posts: n/a
Default Re: DIY Homemade laser diode driver

Daedal - to make it even easier for folks (you have done a GREAT job, BTW) Here is a suggestion - make a basic, non-schematic drawing for folks of what it is you are talking about - label each item, R1, R2, etc....and place a small legend at the bottom....

JUST a suggestion - you have done great work thus far, it may help some folks to visualize the circuit a little better though....
 
Closed Thread





Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


LinkBacks (?)
LinkBack to this Thread: http://laserpointerforums.com/f42/diy-homemade-laser-diode-driver-26339.html
Posted By For Type Date
Laser 530: The diode laser This thread Refback 07-03-2017 05:17 AM
Laser Driver Diy images This thread Refback 06-14-2017 03:42 AM
Laser 530: The diode laser This thread Refback 06-12-2017 09:27 PM
Proiect:Laser de 100-200mW - LED-uri si alte surse de lumina - Forumul Electronistilor This thread Refback 05-15-2017 06:33 PM
Laser 530: October 2010 This thread Refback 03-31-2017 09:12 AM
Laser 530: The diode laser This thread Refback 03-06-2017 01:40 PM
Laser 530: October 2010 This thread Refback 02-25-2017 01:34 PM
zero fidelity CNC: Laser diode driver circuit This thread Refback 02-09-2017 02:09 PM
Laser 530: The diode laser This thread Refback 11-06-2016 06:52 PM
Laser Diode Wiring Diagram - rs232 laser transceiver This thread Refback 10-25-2016 01:37 PM
Laser 530: October 2010 This thread Refback 08-14-2016 01:59 PM
Laser 530: The diode laser This thread Refback 07-14-2016 03:51 PM
Laser 530: October 2010 This thread Refback 07-06-2016 12:59 PM
Laser 530: The diode laser This thread Refback 04-18-2016 02:17 PM
Download DIY Make A 3 Laser Diode Driver Video Mp4 3gp This thread Refback 02-16-2016 08:13 AM
Laser V | Page 2 | OpenBuilds This thread Refback 02-10-2016 12:16 PM
?????-???????? : 300mW Mini This thread Refback 02-07-2016 08:42 PM
Laser 530: The diode laser This thread Refback 12-14-2015 11:57 AM
Laser 530: The diode laser This thread Refback 12-11-2015 01:24 PM
Proiect de week-end: Masina de gravare cu laser din piese ?reciclate? | Blogul lui Iusty This thread Refback 11-22-2015 07:12 PM
zero fidelity CNC: Laser diode driver circuit This thread Refback 11-18-2015 03:42 PM
Diy Burning Laser : CRAFTS This thread Refback 10-19-2015 02:23 AM
Laser 530: October 2010 This thread Refback 10-08-2015 06:20 PM
Diy Homemade Laser Diode Driver 2015 | 123 Sayings This thread Refback 10-08-2015 04:00 AM
Simple Laser Diode Driver Circuit images This thread Refback 09-21-2015 04:31 PM
Laser 530: The diode laser This thread Refback 09-01-2015 05:23 AM
Le moteur de recherche français sans publicité This thread Refback 07-13-2015 05:29 AM
laser diode driver circuit lm358 This thread Refback 07-10-2015 10:24 PM
Pin Diy Laser Diode Driver on Pinterest This thread Refback 06-17-2015 11:56 PM
445nm 1W (1000mW) Blue Brand New Laser Diode in Aixiz Module, HighTechDealZ This thread Refback 06-13-2015 03:24 PM
650nm LPC826 Brand New Laser Diode, HighTechDealZ This thread Refback 06-13-2015 12:00 PM
650nm LPC826 Red Laser Diode in Aixiz Module, HighTechDealZ This thread Refback 06-12-2015 02:06 AM
445nm 1W (1000mW) Blue Brand New Laser Diode, HighTechDealZ This thread Refback 06-11-2015 09:59 PM
DIY: Make a $3 Laser Diode Driver! Musica Movil | MusicaMoviles.com This thread Refback 06-10-2015 12:19 PM
Beginning laser projector build and first post, all advice appreciated This thread Refback 05-07-2015 04:57 PM
laser diode driver circuit schematic This thread Refback 04-25-2015 10:00 PM
Laser 530: The diode laser This thread Refback 03-23-2015 06:12 PM
> circuits > diy homemade laser diode driver l29268 - Next.gr This thread Refback 03-21-2015 06:55 PM
Laser 530: October 2010 This thread Refback 03-16-2015 01:38 PM
> circuits > police laser lidar jammers l34798 - Next.gr This thread Refback 02-16-2015 10:38 AM
Laser 530: October 2010 This thread Refback 02-01-2015 03:34 PM
Laser 530: October 2010 This thread Refback 01-31-2015 03:15 PM
Make Laser Diode Driver This thread Refback 01-12-2015 08:33 AM
Laser 530: October 2010 This thread Refback 01-06-2015 09:39 AM
Laser 530: The diode laser This thread Refback 12-26-2014 07:44 PM
Laser cutter, start slicing stuff for under 50 dollars This thread Refback 12-26-2014 10:42 AM
Magmod Coupon Code 2014 | Mine Craft Online Resource This thread Refback 11-15-2014 10:34 PM
Laser 530: October 2010 This thread Refback 11-11-2014 06:08 PM
Laser 530: The diode laser This thread Refback 10-31-2014 02:34 PM
DIY Homemade Laser Diode Driver Laser Pointers - Searchable.openedhost.com This thread Refback 10-28-2014 01:12 PM










Loading








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes






Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 10:02 AM.


Powered by: vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO
Privacy Policy | Advertising Disclaimer | Terms of Use
Copyright (C) 2017 Laser Pointer Forums, LLC