Seeking advice on purchase

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ple
 
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Seeking advice on purchase

Post by ple »

I would like to purchase two 12 LED rings. I need white-only light in 1 ring and red-only light in the second ring. My project requires constant illumination rather than flickering illumination or color-changes. Is that possible? Will you suggest the products I need to purchase (along with power supply/controllers if any)?
Thank you

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adafruit_support_bill
 
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Re: Seeking advice on purchase

Post by adafruit_support_bill »

For the best white, you should use one of the RGBW rings. For the red only , you could use either the RGB or RGBW
https://www.adafruit.com/products/2853
https://www.adafruit.com/products/1643

You can control these with just about any Arduino compatible from a Gemma or Trinket to a Mega. Will this be battery powered, or will you have access to an outlet to plug it in?

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ple
 
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Re: Seeking advice on purchase

Post by ple »

Thanks! I have added these to my cart. I have an access to an outlet for plugging in, any chance the intensity can be controlled? I am new to LEDs, so forgive my ignorance. Does the PWM 400 Hz frequency refer to some inherent flicker in the light? I found this power supply - https://www.adafruit.com/products/276, I believe that will work although I'd prefer more intensity if possible. Do the Neopixel 5050 RGBW/RGB come with the connectors to the power supply?
Best,

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adafruit_support_bill
 
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Re: Seeking advice on purchase

Post by adafruit_support_bill »

You will also need an Arduino compatible processor to drive them. Something like an Arduino UNO is a good choice for your first project. If space is a concern, we have lots of smaller alternatives too.

You will be able to control the color and intensity with your code on the Arduino. At max intensity white, each RGBW pixel can draw close to 80mA. At max intensity red, it would be 20mA. With one red ring and one white ring at full intensity, that would be about 1.2A. So the 2A power supply should be fine.

The 400Hz is the PWM frequency of the leds. That is fast enough that there is no obvious flicker.

Connecting to the rings will require some soldering. You will need some wire to hook them up. There will be a 5v, ground and a signal connection for each ring.

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ple
 
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Re: Seeking advice on purchase

Post by ple »

I purchased the Arudino UNO and didn't remember to order the power supply! I'll do so now but today I tried using one of my 5V old cell phone power supply to power the NeoPixel via a breadboard. I used a 330 Ohm resistor in series with the ring (assuming the LEDs are in series and need no more than 20 mA each). I connected the positive terminal to the PWR and negative to GND. I didn't have a signal input but I didn't want to control the intensity or anything else. However, the ring didn't light up. Pretty certain I am doing something wrong (maybe bypassing the Arudino isn't a great idea) but not sure what. Appreciate any thoughts on this!

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adafruit_support_bill
 
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Re: Seeking advice on purchase

Post by adafruit_support_bill »

I didn't have a signal input
You can't control them without a signal input. You need an Arduino or similar processor to drive the pixels.

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Franklin97355
 
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Re: Seeking advice on purchase

Post by Franklin97355 »

Take a look at the Neopixel Uberguide for more information.

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