2 weird driver problem

[1d4n]

hi
ive build an laser driver from this site
the 1 with lm317
at first it was working just fine with current set to 330ma
but now i was just curious so i decide to check to voltage and ma
well it show that the output voltage is not 3v its between 6-7.5 volts
isnt it should be 3v?
and second problem
i turn it on
the laser working but after 4-6 seconds the light starting to weaken
until its almost turned off
why is that??
thank you

 

[daguin]

hi
ive build an laser driver from this site
the 1 with lm317
at first it was working just fine with current set to 330ma
but now i was just curious so i decide to check to voltage and ma
well it show that the output voltage is not 3v its between 6-7.5 volts
isnt it should be 3v?
and second problem
i turn it on
the laser working but after 4-6 seconds the light starting to weaken
until its almost turned off
why is that??
thank you

We need more information. What diode? What battery?

Peace,
dave

 

[1d4n]

the diode is 16x red lcc
the battery is 7.2v 2cell li-po

 

[spectral532]

When measuring the output voltage make sure you have a test load connected, otherwise you might get an incorrect voltage reading.

I'm not sure why your laser is dimming out after a few seconds of use. The batteries are fully charged right? You might try hooking up the driver to a alternate power supply and see if you get the same results.

 

[1d4n]

yes the the battery is fully load
and when it dimming the diode is extreamly hot
maybe bacuse of that?
and if yes why the diode wont fry up?
what makes the diode go lower?

 

[spectral532]

The heat might have something to do with it, I'm not sure though. You really shouldn't be running a diode to the point where it's "extremely hot" anyway. If it gets this hot within a few seconds you might be pushing too much current though it.

Have you tried measuring the current while you run the diode? Check the current running through the diode when its at full power vs when it dims.

 

[FireMyLaser]

It is hot because you don't apply heat sinking...

 

[HIMNL9]

Ehm ..... as FireMyLaser say .....

330 mA in a LCC with the bare diode ? ..... if yes, maybe you have burned it (and if it's still working, you're lucky)

Cause you mean that you are trying the diode alone, not in an aixiz module or in any heatsink, right ?

 

[1d4n]

well the weird thing it didnt burn its just dimming after few sconds then i cut the power off
and when im connecting the power again it just start with high light and again dimming
maybe its cos of the heat
btw any1 knows where i can get aixiz model in israel??
i just dont have that aixiz thing

 

[HIMNL9]

Probably ebay is the better solution ..... bu i'm not sure, i know nothing about Israelian custom / import laws. (but aixiz sell 10 modules at a time, mean, packs of 10)

Or any other reseller around here, that you can find in the forum, if you just want one or two of them ..... like modwerx, or similars ..... also some other users sell items here, and maybe they have some to sell, and are more near your place .....


Edit: by the way, this is an aixiz module