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Driver Compilation Thread - All Drivers In Just One Thread!

jander6442

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^ dose it look like this :)

:drool:
 



millirad

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No, but I'll trade what I have for that one LOL. :)
 

millirad

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Ok, I'm running a bit behind on the labby. I finished securing all of the "many" unused wires from the ATX. Snipping unused wires short and putting heat shrink on the ends. I also found the "green" wire that energizes the circuit and tied one end to my installed key switch and a "black" ground wire to the other side. I had to cut a hole in the chassis to install the key switch. Hey, I'll be CDRH compliant to boot. I'll probably use the "gray" wire to install a "power on" LED, with a 330 ohm resistor in series to ground. I'm thinking about painting the drab gray chassis another color. Then I need to finish the 4 X DDL driver circuit board that it drives with 6.9 volts. I'll be shooting for 375ma per ddl driver(a nice low idle current level) so that I'll get 1.5 amps for the 445nm LD. I may install a high/low switch. Low would be 1125ma(3 ddl's switched on), which the LD can easily run at with 30 second duty cycles. And high would of course be 1500ma, which would be used cautiously until I can confirm that it wont kill the LD. ;-)
 
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DrSid

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Ehm .. guys .. feel really stupid to ask .. I'm sure it must be here somewhere .. but I just can't find it. So ..
Where do you buy drivers ? Also is there some DIY laser tutorial ? I built some stuff, but never a laser .. what should I pay attention to ? I hear these laser diodes are pretty easy to destroy.
 

Kevlar

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Ehm .. guys .. feel really stupid to ask .. I'm sure it must be here somewhere .. but I just can't find it. So ..
Where do you buy drivers ? Also is there some DIY laser tutorial ? I built some stuff, but never a laser .. what should I pay attention to ? I hear these laser diodes are pretty easy to destroy.
You can buy some of the best drivers here: http://hacylon.case.edu/ebay/laser_diode/Micro_FlexDrive.php
They are by drlava

You can find good info on the DIY LM317 based driver in this thread: http://laserpointerforums.com/f42/diy-homemade-laser-diode-driver-26339.html

You can also purchase drivers from from a lot of the companies that sell lasers, such as o-like, rayfoss, ect...
 

Kevlar

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Ok, I'm running a bit behind on the labby. I finished securing all of the "many" unused wires from the ATX. Snipping unused wires short and putting heat shrink on the ends. I also found the "green" wire that energizes the circuit and tied one end to my installed key switch and a "black" ground wire to the other side. I had to cut a hole in the chassis to install the key switch. Hey, I'll be CDRH compliant to boot. I'll probably use the "violet" wire to install a "power on" LED, with a 330 ohm resistor in series to ground. I'm thinking about painting the drab gray chassis another color. Then I need to finish the 4 X DDL driver circuit board that it drives with 6.9 volts. I'll be shooting for 375ma per ddl driver(a nice low idle current level) so that I'll get 1.5 amps for the 445nm LD. I may install a high/low switch. Low would be 1125ma(3 ddl's switched on), which the LD can easily run at with 30 second duty cycles. And high would of course be 1500ma, which would be used cautiously until I can confirm that it wont kill the LD. ;-)
This sounds pretty nice, do you have pics?
 

millirad

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^ I will post some pics when all is finished. I have decided to just use 6 x ddl with 3 5 ohm feed back resistors in parallel for each ddl. This produces a somewhat weaker 1100ma instead of the 1500ma I had planned. I noticed that the LM317 regulators were getting warmer than I wanted, so they are running only ~200ma each, which is nothing. You can use many other regulators which easily get you up to ~3 amps with this linear driver, but I wanted something that idled at somewhat cooler temp. without heat sinks.
 

millirad

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So the 6 x ddl only provided a marginal boost in current at 800ma, compared to ~700ma for 4 x ddl. This was running both circuits at 6.9 volts from the ATX, which was produced with +12 volt yellow wire to +5 volt red wire. So then I tried +3.3 volt orange wire to the -5 volt white wire for 8.3 volts, which would give a beginning current of 1500ma, that slowly dropped to ~750ma. So I then just did a quick test of +12 volt yellow wire to 0v/ground black wire. The current held steady at 2300ma. I didn't leave it on for long because that gets my regulators too warm and the dummy load gets very hot. It's also more than I'm willing to put into the 445nm diode. So, I have to drop the +12 volts to ground, to about 7.5 volts and that will give me ~1200ma. This is to keep the regulators from getting too warm. I need to design a voltage divider circuit for this purpose, that will not get too warm itself, and not remove much of the current needed by my driver circuit.
 

HIMNL9

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Uhm, PC PSUs are designed for fixed outputs, and all are related to the ground ..... is not a good idea to use positive and negative outputs, also cause the positive output (3,3V) is designed for high currents, where the negative outputs (-5V. -12V) are designed for low currents (half of the times, the -5V is derived from the -12V with a 7905 regulator ..... usually the -12V is an 800mA max output, and around 500mA for the -5V)

Some old PC PSUs had a trimmer for adjust the 12V output (doing this, also all the other outputs was changing, anyway), but most of the new ones don't use trimmers, but pre-calculated reistor networks ..... if you find one of them, you need first to see what type of IC they use for the control, then with the datasheet, find what is the network that regulate the voltage, and change it (can't post a single schematic "good-for-all", cause there are a lot of them, and any of the different ones, have different configurations and values)

Only, check that they don't use a "power-good" controller IC (usually is an 8 pins IC, marked WT7510 or similar) ..... if there's also this IC, you need to modify the circuit for take away the control signal from it (it turn off the PSU if the voltages go too low or too high)

As alternative, you can also use some big silicon diodes in series with the 12V output, 4 or 5 of them can drop the voltage around 3,5 to 4V, but take care of the currents ..... you need to use high current diodes, and also heatsink them, cause they dissipate all the dropout in heat ..... if you can put your hands on some broken PC PSUs, maybe asking to some PC repair store in your zone, you can probably find some good double diodes in them, in the low tension section, in TO220 format (lots of F12C20C double diodes i have recovered, from them ..... 12A :) ..... but any type can be good ..... if you have a big heatsink, you can also use schottky diodes, that have a dropout of 0,4V, so you need 10 of them, for drop 4V), that can be hooked easily on an heatsink, using their own insulating pads and plastic washers (the tab is connected to the central pin, so they need to be insulated from the heatsink).
 

millirad

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Yes, I realized after researching a little that only +12 volts to ground will be usable. I will need to just drop that down to ~7.5 volts and it will work very well. :) I couldn't think of the correct value resistors for a voltage divider with resistors, so maybe some heavy duty silicon diodes will work.
 
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millirad

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The ATX 445nm laser prototype is complete. I determined that 6 ohms 50watts, in series with the 6 x ddl supplies in parallel was the way to go. This is providing ~1100mw beam and I'm using a 1 minute duty cycle for now. I'm running off of the +12 volt ATX tap to ground. I'm using the 10 ohm 10 watt load from + 5 volt tap to ground as a safety margin. This is my lowered power version, to get some longevity out of the 445nm diode. I need to put the ddl ps into a chassis. I may add more loading resistors to the two 3 ohm 50 watts that are dropping my voltage to the ddl array board. The ddl regulators are all running cool though. Anyway here are 3 pics that I promised.............






 

jander6442

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Thats some clean work... Nice and massive heatsink there. Good job:gj::kewlpics:

.
 

millirad

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Thanks, actually that parallel supply was just quickly prepared to test the feasibility of the design. I built a 7 x ddl that uses a single diode and cap. I really can't feel any heat from the lm317's because of the distributed load. And that is only at ~1100mw, but I think I'll pump it up to ~1400mw with reduced "current sense" resistance.
 

Toke

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I have 20 lm317 inbound by mail, 10 regulars and 10 small ones plus some other components, I also have two hosts prepared for respectively 1 x AAA and 1 x AA.

I will be experimenting with series connecting a joule thief and a linear driver.
It looks like a AAA can deliver 1W maximum, a 1 AA maybe 3W .

It will be fun to see if I can get efficiency high enough. :)
 

millirad

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Ok, I see..... Joule Thief circuit.

 
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Xplorer877

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I've experimented with a joule thief circuit to drive laser diodes. The problem is that they are NOT voltage regulating or current regulating. As the input voltage changes so does the output voltage. It's difficult to calculate load currents and such because it's not smooth DC. It works for LEDs but laser diodes are not as forgiving.

-Tony
 




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