Mitsubishi laser diodes - APC vs ACC
Adrian Pistritto
I have a couple of these mitsubishi 658nm diodes (ml101j18 and
ml101j20). They don't have monitor photodiodes - which leads to
beileve they require ACC drivers.
After reading the FAQ, it seems that ACC is .... for lack of a better
word, crap.
Whats the score here ? the ml101j20 is rated 140mw pulsed, 50mw CW,
i'm hoping to push it a fair chunk higher than its CW rating with a
peltier... will using an ACC driver cause issues due to ambient
temperature variations etc ?
Steve Roberts
living in the higher power region where current control is standard, I
have found that the ACC type data sheets are pretty much honest, APC
devices often can be "pushed" a bit, but if acc says 250 mA max, then
well, its 250 mA max.
the mitsu devices are not bad and their datasheet is right on the
mark, it doesnt have the usual "factor of two" engineering overkill.
Its more like a 10% reserve.So if you can suck more heat out of it,
sucessfully, then you can go back down the curve a bit, but not much.
Steve Roberts
Sam Goldwasser
Really depends on what the limit is. If it's COD, then heat doesn't matter.
In fact, if you cool it with ACC, power goes up and it may go poof.
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LesioQ
The only meaningful explanation that comes to my mind is Cash On
Delivery abbreviation. But APC ? ACC ? Let me join Your club, please !
:-)
LesioQ
Sam Goldwasser
APC: Automatic Power Control, i.e., constant power mode.
ACC: Automatic Current Control, i.e., constant current mode.
Jasper Janssen
wrote:
>APC: Automatic Power Control, i.e., constant power mode.
>ACC: Automatic Current Control, i.e., constant current mode.
And COD?
You wrote earlier:
>Really depends on what the limit is. If it's COD, then heat doesn't matter.
>In fact, if you cool it with ACC, power goes up and it may go poof.
I took it from context that it refers to the limit where you blow the
output facet off the diode?
Jasper
Adrian Pistritto
the f..cking lasre faq) ;)
hmm. on that note, the mitsu diode ml101j20 have a cw 50mw rating, and
a pulse 140mw rating. from this can one read that if the heat can be
sucked out of it, the thing could be driven in cw mode in the low
100's of mw ?
Piotr.K...@stream.pl (LesioQ) wrote in message news:<1ed6861.04031...@posting.google.com>...
rick
"Jasper Janssen" <jas...@jjanssen.org> wrote in message
news:3bec501ruttg0d92o...@4ax.com...
> On 15 Mar 2004 15:53:02 -0500, Sam Goldwasser <s...@saul.cis.upenn.edu>
> wrote:
>
> >APC: Automatic Power Control, i.e., constant power mode.
> >ACC: Automatic Current Control, i.e., constant current mode.
>
> And COD?
catastrophic optical destruction (if I spelled that right)...sometimes refered
to as LSO (let the smoke out)
Sam Goldwasser
> ACC and APC - auto current control and auto power control. rtflf (read
> the f..cking lasre faq) ;)
>
> hmm. on that note, the mitsu diode ml101j20 have a cw 50mw rating, and
> a pulse 140mw rating. from this can one read that if the heat can be
> sucked out of it, the thing could be driven in cw mode in the low
> 100's of mw ?
This is what I would expect. Since COD (Catastrophic Optical Damage)
is sub-nanosecond, other effects are likely thermal. If it can be
kept cool enough, could work much above the CW rating. There will
be a COD rating as well probably slightly above the pulsed rating.