LED Strip Controlled by Rasp Pi

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jebuk201
 
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LED Strip Controlled by Rasp Pi

Post by jebuk201 »

Hello,

I am looking to connect a Flexible RGB Neon-like LED Strip 120 LEDs - 1 meter long Product ID 4245 to a raspberry pi 3. I understand that it needs a 12 VDC 1A power supply. I would just like to know how it connects to the raspberry pi and how to control or program it.

Thank You,
Joshua

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dastels
 
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Re: LED Strip Controlled by Rasp Pi

Post by dastels »

You can use something similar to the example I did here: https://learn.adafruit.com/transistors- ... -3001921-1. You would need 3 transistors, once each for red, green, and blue.

Dave

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jebuk201
 
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Re: LED Strip Controlled by Rasp Pi

Post by jebuk201 »

Hi,

Thanks for sending that. Is it critical to have a resistor or no?

Thanks

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dastels
 
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Re: LED Strip Controlled by Rasp Pi

Post by dastels »

Yes. the resistor controls the amount of current flowing through the base-emitter junction. That's what lets you control the on/off action of the collector-emitter junction. Also it limits the amount of current used from the GPIO pin which is quite limited. That's another reason you need to use a transistor to control the LEDs, in addition to switching the higher voltage.

Dave

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