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ArcticMyst Security by Avery

2 Volts with boost drive

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I'm assuming it won't work but I have a led flashlight I want to use as a host and according to my multimeter its putting out 2 volts to the led. The battery is 3.6 volts rechargeable made out of 3 smaller batteries. The microboost driver is set at 1 amp.

Is 2 volts enough? The host is perfect so I'm hoping it will work.
 





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A boost driver takes the 3.6 Volts of the battery and
BOOSTS it to a higher level.... not lower...

A little research and reading on the Forum would help
you to use the correct terminology and it would easily
answer your voltage/Laser Diode question...


Jerry
 
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I understand that. What im saying is that at the led the voltage is dropped to 2 volts not 3.6 volts. I want to wire the laser in place of the led because it has a built in battery charger. I know the 3.6 volts works just fine ive just never heard of anyone running as low as 2 volts and I dont want to mess up the driver with low voltage and force it to draw high amps to boost it. I just dont know if 2 volts is enough. Its an easy yes or no question I just cant find my microboost manual.
 
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A quick search of the Diode Compilation thread should give you the answer you seek.
 
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A boost driver takes the 3.6 Volts of the battery and
BOOSTS it to a higher level.... not lower...

A little research and reading on the Forum would help
you to use the correct terminology and it would easily
answer your voltage/Laser Diode question...


Jerry

Now you're just being silly, why would a driver that boosts the voltage be called a boost driver?

We drive on a parkway and park on a driveway.
When you transport something by car it is called a shipment, but when you transport something by ship it's called cargo.

Don't you ever let me catch you making sense again young man.
 
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Now you're just being silly, why would a driver that boosts the voltage be called a boost driver?

We drive on a parkway and park on a driveway.
When you transport something by car it is called a shipment, but when you transport something by ship it's called cargo.

Don't you ever let me catch you making sense again young man.

ROFL....:crackup::crackup:

But so true...:evil:

Jerry
 
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I was looking at dc to dc converters last night. It made reference to Buck boost.
They can also be used to drop voltages too.
So.....does that make it a debooster or an unbuck driver? :crackup:
Maybe even an unbuckled driver???? :eek:
 
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DrSid

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If it puts 2V to the diode from 3.6V, it's not a boost driver.
445nm diode needs about 4V (depending on power required), so from 3.6V it would need boost driver.
 
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If it puts 2V to the diode from 3.6V, it's not a boost driver.
445nm diode needs about 4V (depending on power required), so from 3.6V it would need boost driver.

That's what I thought at first, because the OP did a horrific job at explaining what he wanted, which led to the confusion. (sry pun hehe)

He wants to connect the input of the microboost to the driver that the flashlight comes with (which puts out 2V for the flashlight's led) I told him the microboost needs a minimum of 2.7V to operate.
 
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One thing the OP didnt state or show a pic was the type of small battery. If its 3.6V from 3 batteries.....hmmmmm.....3 button cells or AAA's would be 4.5V. 3 AAA rechargeables should be 3.75V.
If its the 3 AAA "pill" it could be changed to 3 Li-Ion 10440's and should have sufficient input.
I don't want to be to hard on the OP. He only has 32 posts and he does seem to be trying.
One feature of the search on the forum I found "trying" is that if the word you search is someones name, part of it or the string occurs in it you get all of that persons posts to go through. Hmmm...I didn't think to try advanced to see if the name can be excluded...duh...

Edit: I re-read the OP. He said rechargeables. If he is using NiMH the internal resistance may not allow them to dump the 1A being asked for reducing the output voltage. He really needs to get a proper microboost it sounds like. If its a flashlight "microboost" it may have the Vf limited to 2V for the output. To many possibilities and assumptions being made.
 
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Is this LED white? I've never heard of a white LED dropping only 2V. Red, maybe, but not white.
 
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One thing the OP didnt state or show a pic was the type of small battery. If its 3.6V from 3 batteries.....hmmmmm.....3 button cells or AAA's would be 4.5V. 3 AAA rechargeables should be 3.75V.
If its the 3 AAA "pill" it could be changed to 3 Li-Ion 10440's and should have sufficient input.
I don't want to be to hard on the OP. He only has 32 posts and he does seem to be trying.
One feature of the search on the forum I found "trying" is that if the word you search is someones name, part of it or the string occurs in it you get all of that persons posts to go through. Hmmm...I didn't think to try advanced to see if the name can be excluded...duh...

Edit: I re-read the OP. He said rechargeables. If he is using NiMH the internal resistance may not allow them to dump the 1A being asked for reducing the output voltage. He really needs to get a proper microboost it sounds like. If its a flashlight "microboost" it may have the Vf limited to 2V for the output. To many possibilities and assumptions being made.

Its a simple question. If I didnt state it clearly enough im sorry. Congrats on 225 posts....im not worthy I guess :bowdown:

Forget the battery and im not using a "flashlight microboost" I dont think that even exists. Im using a microboost...like a microboost diver...literally the only relevant component I have ever heard of called a microboost. Not sure how that was confusing.

The battery is 3.6v but it has internal circuitry for the built in charger and to drop the voltage im assuming. At the leads that connect to the original LED the voltage reads 2v. So the original question was will 2v be enough to power the microboost set at 1 amp? I wanted to just wire the driver and diode in place of the led.

I now know that it is not.
 
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DrSid

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Well then those 2V are most probably result of current driver feeding the diode. The voltage might be totally different with different thing plugged into it. It's really hard to tell.
 
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if you are using the microboost, you don't need to use the flashlight driver. Sounds like a crappy driver anyways if it's feeding the LED 2V from a 3.6V source.

Basically, microboost takes X amount of power from batteries and sends that same X amount of power (minus driver inefficiencies) to the laser diode. If the batteries don't have enough voltage to drop across the laser diode, it pulls more current so that it can boost the voltage.

If you are a math-minded person, perhaps these equations will help:
It's a given that Power = (Current)*(Volts), or
Code:
P=I*V
Power from the batteries (Pin, as in P-sub-in) equals power to the diode (Pout), so:
Code:
Pin=Pout
substituting for Power, we get:
Code:
Iin*Vin=Iout*Vout
To explain the variables, Vin is the voltage that the battery supplies. Vout is the Vf of the laser diode at the current that you want to run it at. You can see that if the Vout is higher than Vin, the driver will need to pull more amps from the battery than it sends through the diode.

For example, let's say you are running a diode with a Vf of 6V@1A, from a 3.6V battery.
3.6V*Iin=6V*1A
Iin will be ~1.7A for the driver to supply the 6V at 1A to the diode. That means you better make sure your battery can supply 1.7A safely for this particular situation.

These equations are for your understanding, but do not take into account driver inefficiencies.
 
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Yes, bypass the crap in there. It can't be that hard. Whatever it's doing to the power source, it's not adequate for a laser application.
 




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