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ArcticMyst Security by Avery

AC power supply

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I have two very stable power supplies, one 5.2vcc / 800ma and another 5v / 350ma.
the question is: using the casio a140 diode, and the two power supplies in paralel, what would happen? :) 5.1vcc @ 1150ma (1.15amp)?
thanks in advance.
 





udanis

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Well they are two different voltages so you risk blowing out one of them. Same thing happens if you try and run two different dc voltage regulators in a circuit.
 
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well I see..
what the.. you again answering my threads? O_O jk.
thanks again man.
 

udanis

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Well it's either paying attention in Humanities 201 or answering laser questions :D
 

Benm

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Dont run voltage sources in parelel, and don't use voltage supplies to power laser diodes - double fail eminent :D
 
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Dont run voltage sources in parelel, and don't use voltage supplies to power laser diodes - double fail eminent :D

O_O why don't use voltage supplies to power lds? what the... O_O
(I didn't used any voltage source in parallel)

:beer:
 

udanis

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O_O why don't use voltage supplies to power lds? what the... O_O
(I didn't used any voltage source in parallel)

:beer:

Because usually they can not put out constant enough power. Usually there are fluctuations in it.
 
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Leodahsan;

All DC supplies will deliver more than their rated current.

1st of all, make sure the 445nm diode has a large heat-sink.

Then hook up the 800ma supply with a 1 ohm resistor (1 watt) to try.

The current will be lower than 1 amp. Check the value.

Lower the 1 ohm slightly with a 4.7 ohm in parallel.

The current should increase slightly (10-15%).

Let it operate for a few minutes to stabilize.

It is basic experimentation !!

Larry
 
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It's not entirely true that you can't use an AC-DC power supply to power your laser. However, unless you're buying an audio-quality power supply, which is already regulated for filtering out noise and spikes, you need to have a regulator circuit in between, like a traditional LM317 regulator circuit (aka a DDL circuit). Another problem is that most AC-DC transformers don't provide sufficient current for powering higher-current lasers. I wasn't able to use mine for testing a 445nm on its dummy load, so I had to attach it up to the batteries which was a pain.

If you'd like to power your laser from the wall, buy a 9VDC wall-power supply, and a DC Barrel Jack. Then you need to connect the barrel jack to a regulator circuit such as a DDL circuit for actually connecting to your laser. I've also used this breadboard power supply for simply providing 5V regulated voltage for various projects, including lasers. It has nice clean power, and can be modded into a DDL circuit as well with some modifications (I haven't actually performed the mod yet).

Never use two voltage sources in parallel unless they're matched (i.e. have exactly the same voltage characteristics). Usually only specially selected batteries from the same production batch can be connected in parallel to provide higher current and capacity. The reason not to? There will be a voltage difference between the two batteries and the batteries will "fight" each other as they try to equalize the charge between them. This can damage the batteries and possibly cause a lot of heat from the rapid flow of charge between the two batteries.
 
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omg. :)
thanks for the help ppl.
if there is anything that I don't know, anyone can post here.
 




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