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ArcticMyst Security by Avery

Need to amplify this

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Jan 12, 2008
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woop said:
so with your crazy flashing board, its active low right? so it connects the led to ground to turn it on?
thats what that circuit is made for

I'm sorry, what? I don't know... :-/



I looked up N-FET and I can't find any in this country. Is this some brand new technology? And what does SEC mean (I think I got something), or is it just random?
 





phenol

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in your case you need n-channel MOSFET. Since it is only going to be used for switchin, it doesnt necessarily have to be a high power one, as long as the turn on resistance is low and it has adequate current handling capability. Another important parameter to consider is the threshold voltage - for sure it has to be lower than the turn on voltage you are going to apply on its gate.
Furthermore, if turn on and turn off speeds are of little significance (<hundreds of kHz, that is), you can drive the gate directly or thru a resistor, should your pulsing circuit be incapable of handling capacitive loads.
Here's a nature-friendly one, suitable for low voltage operation: IRF7460PBF. If you cant find it locally, try looking into another IRF one. Those are quite popular.
 
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Pick one. ::)

IRFZ44N TO-220 N-ch MOSFET 55V 49A

IRFZ48N TO-220 MOSFET N-ch 55V

IRFR110ATF TO-252 N-ch MOSFET 100V 4.7A

IRFP240PBF TO-247AC N-ch MOSFET 200V 20A

IRF530N TO-220 N-ch MOSFET 100V 17A

IRF540 TO-220 N-ch MOSFET 100V 28A

IRF630 TO-220 N-ch MOSFET 200V 9A

IRF720 TO-220 N-ch MOSFET400V 3.3A

IRF840 TO-220 N-ch Power MOSFET 500V 8A

IRF510A TO-220 MOSFET 100V 33W 0.2ohm
 

phenol

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i picked 2

IRFZ44N TO-220 N-ch MOSFET 55V 49A

IRFZ48N TO-220 MOSFET N-ch 55V

both look promising and rather beefy
 
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IRFZ44N TO-220 N-ch MOSFET 55V 49A is halve the prise. About $3,4 each.

Now, will this work with common anode and 3.5V pulse?
 

woop

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so when you say common anode you imply that the led's are connected to +3.5V and the flashing circuit connects the led's to ground to light them up?

that is what i designed that circuit for, so your flashing circuit can drive it.

basically is this how it works. (imagine the switch is your chip)
 

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Joined
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The RGB keychain circuit kinda looks like this:

I've marked out the voltages and where the 3V (give or take) the pulses are.

rgbic-1.jpg
 

woop

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ok, so when the pulse is low, the led turns on. thats what i was asking.
cool that circuit i made should work
 




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