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ArcticMyst Security by Avery

My first 445 diode schedule question

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Sep 24, 2010
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Hello i am new here
Ive 1 question
Is this schedule good enough for the XJ-A140 i recently ordered
( not yet received ) I designed it myself and i just want to make sure that i won't blow up the diode because i wait for that already more then 1 week and i really want to be sure nothing goes wrong with my first 445 laser

5d3rsm.jpg


And already i say thank you for the help

Greetings bas
 





HIMNL9

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As principle of work, the schematic is ok, but you need some decoupling resistors from mosfet to op-amp, for make it work more stable and less critic ..... also, maybe is better to use a more stable voltage reference than a 7805 .....

If you want, can try my version (supposing you are building a labby unit)

3355-himnl9s-crazy-generical-lab-type-current-sink-analog-modulable-laser-diode-driver-p.jpg


Just don't mount the components in red, if you don't need it modulable.

Also remember, all the unused voltage is converted in heat from the mosfet, so, as principle:

1) Always choose a low-RdsON model (power mosfets, HEXfets and also better, TrenchMOS units have internal RdsON in the range of millivolts), with low voltage (35 or 40 V are more than enough) and high current rate

2) Always try to use a lower power supply voltage, near the one required from the diode, so there's less power to convert in heat (as example, for a 445nm with 5V FV, you can use 9V, or also better 7,5V, as power supply, so the MOS need to dissipate less heat)

3) Always heatsink the mosfet ! ;)
 
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Thank you for this schedule! i will use it , and when it all burns nice and bright i will post pictures and videos =)
 
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well well it's Bright pretty only the beam is a lil disappointing get's really wide after like 30 feet but for the money i give the laser a B it burns nice fast @ 700mA and i am a lil affraid to crank it up till 1100 lol scary anywhay thanks for the help and when ever i have some nice pics ill post some in Multimedia section ciao :)


little burn demo after i got the laser monday quickly i connected it to see the blue power
http://www.youtube.com/watch?v=rAYUB9YCq2s yeey !
 
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