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Sentorch diodes?

jayrob

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Gazoo, are these the drivers you are talking about?
http://www.dealextreme.com/details.dx/sku.3160
They are advertised 3.6v to 4.5v input and regulate 350mA output current. They don't say how many volts the output is though??
Jay

P.S. What kind of power are you getting out of the open can diode at 350mA?
 

Gazoo

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Yup, those are it. The amount of voltage they put out will depend on the resistance of the device being driven, but the current will always be around 350ma's.

I am getting ~240mw's output.
 

jayrob

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Gazoo said:
Yup, those are it. The amount of voltage they put out will depend on the resistance of the device being driven, but the current will always be around 350ma's.

I am getting ~240mw's output.
This sounds like a great project! I've got everything ordered. I am guessing that if you can maintain proper cooling with the peltier, then the run time can be indefinite? Looking forward to this! Thanks for your help...
Jay
 

Gazoo

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The DX regulators make everything much easier and are perfect for the open cans. For the peltier the DX regulator should be ok too as long as your ambient temp. is less than 80 degrees with normal humidity.

Unfortunately, no one has been able to find a data sheet for the open can diodes. I am guessing they should last a very long time running at 350ma's. But I would still keep the run time restricted to a reasonable amount.
 

jayrob

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Gazoo said:
The DX regulators make everything much easier and are perfect for the open cans. For the peltier the DX regulator should be ok too as long as your ambient temp. is less than 80 degrees with normal humidity.

Unfortunately, no one has been able to find a data sheet for the open can diodes. I am guessing they should last a very long time running at 350ma's. But I would still keep the run time restricted to a reasonable amount.
It sounds like your making this very easy for me Gazoo...Just the two AMC7135 drivers (one for the LD and the other for the peltier), with nothing else? And these two drivers are being powered by 4 AA rechargeables in series? Or maybe a couple of CR123 in parallel?
Jay
 

Gazoo

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4 Nimh AA's will cause the regulator to get too hot and so will 2 CR123's. However it would run on one RCR123 as long as the battery is rated to handle at least 700ma's of current.

I am only using 3 nimh AA's to power everything... :) The only other component I am using is a 10mf 16 volt capacitor which I soldered directly to the laser diode.
 

Gazoo

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Yes but you need to put a 33 ohm 1/2 watt resistor in PARALLEL with the diode. The 33 ohm ohm resistor will absorb appx. 100ma's ;)
 

jayrob

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Gazoo said:
Yes but you need to put a 33 ohm 1/2 watt resistor in PARALLEL with the diode. The 33 ohm ohm resistor will absorb appx. 100ma's ;)
Hey Gazoo, for future reference, please give the formula for this resistance...is it just the current (350) divided by the 33 ohms? Also, by 'parallel' you mean in-line on the positive lead before the LD correct? (not too sharp with electronics, I learn as I go)...
Thanks,
Jay
 

Gazoo

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I did not use a formula to figure it out..it was a lucky guess.

By parallel I mean across the diode..the ends of the resistor get soldered to the legs of the diode just like the capacitor does.
 

jayrob

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Gazoo said:
I did not use a formula to figure it out..it was a lucky guess.

By parallel I mean across the diode..the ends of the resistor get soldered to the legs of the diode just like the capacitor does.
I built a little projector like rog8811 showed...I experimented with puting a 10 ohm resistor before one of the motors because I was trying to get the other (pot controled) motor to be able to adjust faster or slower. I put the resistor in-line on the positive lead and it worked! Should I have put the resistor in parallel?
http://www.laserpointerforums.com/forums/YaBB.pl?num=1186862602/45
Jay
 

jayrob

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Gazoo said:
4 Nimh AA's will cause the regulator to get too hot and so will 2 CR123's. However it would run on one RCR123 as long as the battery is rated to handle at least 700ma's of current.

I am only using 3 nimh AA's to power everything... :) The only other component I am using is a 10mf 16 volt capacitor which I soldered directly to the laser diode.
Gazoo, another question...You are using the 1.7 volt AMC dirver for the open can diode at 350mA, I am going to use an adj. current DDL driver for my open can, do you think I am at risk here with the voltage? Or, can I asume that the open can diode will use the same 2.8ish voltage as the Senkat diodes and be fine?
Jay
Man!...'240mW at 350mA'!!! That's awesome. I just ordered two more DVDs. I want to put an open can in one of my MXDLs with the aluminum heat sink at 323mA...What do you think? Short duty should be ok huh?
 

amkdeath

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jayrob said:
[quote author=Gazoo link=1196802322/15#24 date=1196831564]Yes but you need to put a 33 ohm 1/2 watt resistor in PARALLEL with the diode. The 33 ohm ohm resistor will absorb appx. 100ma's ;)
Hey Gazoo, for future reference, please give the formula for this resistance...is it just the current (350) divided by the 33 ohms? Also, by 'parallel' you mean in-line on the positive lead before the LD correct? (not too sharp with electronics, I learn as I go)...
Thanks,
Jay[/quote]


Amps= sqrt(watts/ohms)

= sqrt(.5/33)
__
= sqrt(.015151515)
=.123
absorbs 123 mA

BUT

using that same formula,

if I use a 47ohm resistor,

=sqrt(.5/47)
=sqrt(.010638)
=.103

that absorbs only 103 mA as opposed to 123, and I want this diode to be powerful, so I think 47ohm 1/2 watt would be a better option.

also, you said these circuits run on only 1 CR123? I gather RCR-123 is a rechargable 3.6v version of CR123? so would 2 CR123 3.0v NON rechargables in series power this thing? thanks,

amk
 

a_pyro_is

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amk, I'm not certain it would work that way, I think you'll need to figure the LD Vf / Ohms = how much current the resistor will 'steal' from the LD.
But honestly, I don't remember all that stuff...I'll just be experimenting to figure it out myself.
 




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