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Need help finding a mosfet board

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M11C

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Hello

I need help finding a mosfet board that uses N-mosfets and switches using a negative signal.

it's for RGB LED amplification, and i could use one form Ebay, if it wasn't for the fact that my controller uses voltage control (not PWM) to change the brightness of the channels (color), an i haven't been able to find a varaiable gain amplifier.

the only thing i could find in that regard was a VCA810 chip, but i'm not even sure it does what i'm asking, and i still need a PCB.

anyway, back to the mosfet board. this one i have would otherwise be perfect:
**broken link removed**
if it wasn't because it uses a positive signal to open the gate on the mosfet.

I hope you guys can help me.
 
You want to amplify LEDs? To make them sound louder? Oh, you want to adjust the levels of the red, green and blue to change the total color.
The brightness of an LED is controlled by its average current, not by its voltage. But if you add a resistor in series with an LED and feed a changing voltage to them the result is brightness control. A transistor or Mosfet can feed the voltage that is controlled by feedback from an opamp. Since your controller uses a changing negative voltage then it can feed the cathodes of LEDs that have series resistors connected to the 0V.

Can your controller (please post its datasheet) provide enough output current for your LEDs? How many LEDs do you want to control?
 
The brightness of an LED is controlled by its average current, not by its voltage. But if you add a resistor in series with an LED and feed a changing voltage to them the result is brightness control. A transistor or Mosfet can feed the voltage that is controlled by feedback from an opamp. Since your controller uses a changing negative voltage then it can feed the cathodes of LEDs that have series resistors connected to the 0V.

uhmm, no? i dunno, i would just think voltage regulated the brightness, causing current to lower... OHM's law and all that.

the only datasheet i could find is this one:
www.corsair.com/~/media/Corsair/download-files/manuals/link/CommanderMiniQSG_Eng.pdf

I'm looking to power 5m of 5050 LEDs, so 300 LEDs total, drawing around 5 amps.
 
Looks like proprietory connectors on that Corsair controller. Do you have the necessary matching connecting lead for the LED1 output connector?
Can you post a link to the datasheet for those LED strings?
 
Ohm's Law works with a resistor whose current doubles when its voltage is doubled.
But an LED is a diode whose current doubles and destroys it when its voltage is increased a little and if you feed it an accurate voltage its current increases and destroys it as it warms up which makes it hotter which increases its current which makes it hotter which increases its current etc.

EDIT: You are using LED strips that already have the required current-limiting resistors built on them. That is why they use 12V instead of the much lower voltages used by LEDs. 12V= full rated brightness. 1.8V to 3.5V= fairly dim.

Edit again: They might have 3 LEDs in series and in series with a current-limiting resistor then they are fairly dim when the voltage is 5.4V to 10.5V but at full rated brightness with 12V.
 
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Looks like proprietory connectors on that Corsair controller. Do you have the necessary matching connecting lead for the LED1 output connector?

It's molex and yes, i do.

EDIT: You are using LED strips that already have the required current-limiting resistors built on them. That is why they use 12V instead of the much lower voltages used by LEDs. 12V= full rated brightness. 1.8V to 3.5V= fairly dim.

Edit again: They might have 3 LEDs in series and in series with a current-limiting resistor then they are fairly dim when the voltage is 5.4V to 10.5V but at full rated brightness with 12V.

this really didn't answer my original question...
 
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