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ArcticMyst Security by Avery

Empty DX lasers as hosts...

Joined
Feb 5, 2008
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Thanks,

appreciated :)
Oh yeah I forgot some things:
Diagram (schematic) same as DDL driver, except a 1117 is used instead of 317, without potenciometer , 2x 10 ohms (those resistors and a pot is a stupidest thing I've ever heard), only 12 ohms of resistance TOTAL between OUT and ADJ,

Minimum input voltage = Vf of laser diode, plus Vdrop of a driver
meaning: 5 V + 1.4 V = 6.4 V
Fully charged 10440 is 4.2 V, 8.4 V total
average is 3.7 V, 7.4 V total

Minimum voltage is 3.2 V, 6.4 V total.

Aprox runtime ~ 2 hours on one charge .
 





aXit

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My mistake, I only looked at the date on TheDeviation's post.

Now, what you're saying about the LM1117 is wrong.

The Vdrop you're quoting as 1.4V, it is actually 1.2V at 100mA.

That value is for voltage regulation; when acting as a constant current source, the reference voltage is also has to be dropped of the input voltage, in this case a further 1.25V.

It is impossible that using a 1117, that you're getting 1.4V minimum drop.
 
Joined
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Messages
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My mistake, I only looked at the date on TheDeviation's post.

Now, what you're saying about the LM1117 is wrong.

The Vdrop you're quoting as 1.4V, it is actually 1.2V at 100mA.

That value is for voltage regulation; when acting as a constant current source, the reference voltage is also has to be dropped of the input voltage, in this case a further 1.25V.

It is impossible that using a 1117, that you're getting 1.4V minimum drop.

Dude, that is even better!
I always like to ensure myself by reffering to 'worst case scenario', meaning the highest Vdrop stated anyhwere, due to temperature or whatnot.

So, where is the problem?
 

aXit

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Dude, that is even better!
I always like to ensure myself by reffering to 'worst case scenario', meaning the highest Vdrop stated anyhwere, due to temperature or whatnot.

So, where is the problem?

When I say "a further 1.25V" it's added on...

So 2.45V minimum.
 
Joined
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Jeez dude, please don't bump this old thread.

Out of two bluray lasers build using only two ali-ion cells and 1117, both are awsome burners and have excellent visibility for a bluray.

Just yesterday I was interested in exact current measuremet. Took apart my bluray in duracell host, and grabbed a crocodile clamp cable .
Each of batteries measured 4.10 V.

Crocodile clamp cabel has 2.5 ohms of resistance, and probes of multimeter have 0.5 Ohms (measuring clamps therefore shows 3 ohms flat, only probes are 0.5 flat :D)

Now, I attached a crocodile clamp, on end of negative contact (switch), and used DMM to measure the current between positive of battery and positive contact.
DMM set to 10 A,
LCD screen read : 0.10
In yo' face!

Total battery voltage is 8.20 V, and votage drop on crocodile clamp is about 1 V.
Therefore, ~7V is more than enough to run it.

Do we need to continue this pointless discussion?
 

aXit

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No, there is no reason to continue, because you still won't listen.

Oh well, enjoy your lasers.
 
Joined
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Dude I have 100mA current flow with less than 7 V ...

What is there to listen? You are telling me that my laser does not work?
I am sorry I just though that insanely bright nice violet color dot lightning the matches is my laser...
I must have mistaken then!

Dude, do I have to record it on video for you?
Why won't YOU listen?
 




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