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ArcticMyst Security by Avery

CR123A housing HAS blue ray.

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Re: CR123A housing awaits blue ray.

Thanks for the answer catdog. About what I was expecting. I had hopes since someone mentioned the V-drop was only 1.7v. If I read you right, we have to account for another 5v in current regulator mode.
So it's just a 5v reference.

Then the lm317 is more efficient with a Vdrop of 1.7+1.25= 2.95v
I guess I'll just have to get a lm317 in TO-92 package. But where to find the extra 1 volt from my batteries.
 





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Re: CR123A housing awaits blue ray.

Will this work? LDO dual 5V regulator. If I read the datasheet right, the 5v standby regulator has a maximum current of 50mA which should be pretty safe for the BR diode. and the dropout voltage is only 0.55v meaning 2xCR123 primaries or more can be used. TO-220 package though.

Any thoughts?

10pieces if it is good we could share them or sth.
http://cgi.ebay.com/10pcs-SG29055P-...oryZ4663QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
 

Gazoo

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Re: CR123A housing awaits blue ray.

It looks good to me and having the other output is a plus. One output could power the blu-ray, and the other output could power the red..this does have possibilities. But, I don't know yet what the knee will be on the laser diode. I ran mine at 47ma's which was equal to 4.99 volts. Anyway, the max dropout voltage of the regulator appears to be .7 of a volt...much better than either the 7805 or 317.
 
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Re: CR123A housing awaits blue ray.

I just spent the past half hour or so poring over LDO regulators with low outputs. I actually found another 5v 50mA regulator but it was SOT23 package meaning super small smd shitz

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=140123279735&ssPageName=STRK:MEWA:IT&ih=004

Can't wait for a typical I-V graph to come out on these diodes. Did Mike say he was going to do one?

47mA - 4.99v gazoo
41mA - 4.90v zarniwoop
40mA - 4.68v hemlock_mike
40mA - 4.6v DDL recommendation

If I pump 5V without any current regulation, it shouldn't draw more than 50mA and still run pretty safely right?
 
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Re: CR123A housing awaits blue ray.

My first Blu draws 40 mA at 4.68 volts.  
I'll be interested to see how much you get at 5 volts.
My graph indicates potentially 60 mA but all diodes vary at the high end.

Mike
 

Gazoo

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Re: CR123A housing awaits blue ray.

Mike, I see there is quite a difference between the voltage you apply and mine. Interesting. The differences in current vs voltage could be on account of our meters. I am measuring mine with a 1 ohm resistor in series with the diode, and measuring the voltage across the diode to get my current reading. I will need to check with my LPM-1 to see if we are in the same ball park.
 
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Re: CR123A housing awaits blue ray.

Nice find Gazoo. $1.85 shipping is very decent and I am sure they combine shipping on such miniscule items. The only thing putting me off is my inability to solder this thing. They are like 3x2mm according the the spec sheet. He does sell 47uf 25v electrolytics at $0.09 a pop too.
 

Gazoo

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Re: CR123A housing awaits blue ray.

Yup...he only charges a penny for each additional...I know it is tiny and would be a pain to solder, but I think it would be worth it. And I bet it doesn't heat up much either. This would be my other concern since I am planning on using a 9 volt battery for now. But 40 to 50 ma's isn't much current.

It just might be perfect, and the whole circuit could fit inside a standard Aixiz module. But one would need to use small wires. I really feel 10uf 16 volt capacitors are sufficient if running on battery power...it's what I have been using. So should I be the guinea pig and order a few of these... ;D
 
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Re: CR123A housing awaits blue ray.

Gazoo --

I measure my current with the meter in mA mode. Your method is good too but I think some have put the meter across the "shunt resistor" with the meter in mA mode :(

The LPM is not calibrated at 405 nM and I think it will read a little low in the 473 nM setting.
At 40 mA, My LPM reads 9.00 mW.

Mike
 
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Re: CR123A housing awaits blue ray.

He's selling some smd caps too if you are adventerous. From the spec sheet iirc 1.0uf or 2.2uf is sufficient and the esr range is pretty large too. Gazoo do you have circuit boards to actually mount these on? Sent you a pm.
 

Gazoo

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Re: CR123A housing awaits blue ray.

Mike,
Measuring current with my meter using the 100ma. and 10 amp scale will give me different results. You are probably right that some misunderstand how to measure current using the 1 ohm resistor.

I have my ND filter taped to my LPM with double sided sticky tape and I do not want to remove it until I find a better solution. But with the filter, I am reading 6mw's output at 40ma's.
 

Gazoo

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Re: CR123A housing awaits blue ray.

xarylx,
I am not that adventurous...lol. I mean soldering the wires to any SMD device is a pain but can be done. And I don't have circuit boards to mount these on. If I were test these, the way I would do it would be to test one with one of the 50 ohm trim pots I ordered, then take it from there.

I would not want to run more than 40ma's into the diode...I think this is the maximum to be safe for a long lasting diode, and it isn't that much brighter running at 50ma's. If I was to go as high as 60ma's, then I would think about using a TEC and go with the LM317 to adjust current. Like Mike said, we really don't know what the maximum current is we can safely run these at....these diodes are very new to us.
 
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Re: CR123A housing awaits blue ray.

Hmmmm.... I have got some 7805's on the way, if I have read the above correctly I can try it as constant voltage and use the pot to adjust current?..... need to get off to work now, I will look at this again this evening.

Regards rog8811
 
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Re: CR123A housing awaits blue ray.

I had the impression that wouldn't work unless your Vin is 12v
 

Gazoo

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Re: CR123A housing awaits blue ray.

It will work with a minimum voltage of 6.7 volts when used as a voltage regulator. It has a drop out voltage of 1.7 volts. Since Rog will be using 2 RCR123's, it will run the laser for a long time before he needs to recharge them. Even running with a 9 volt battery it should run a good long time.

I think I am going to wait until I get my 7805's before I decide to order more parts. The other regulator is nice with its low drop out voltage which is negligible, but it is difficult for me to solder components that small.
 




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