TLC5947 LEDs in Series Questions

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TheWolf_79
 
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TLC5947 LEDs in Series Questions

Post by TheWolf_79 »

Hi, I am interested in using the TLC5947 breakout board to drive a bunch of RGB LEDs. I want to put 5 LEDs in series on each output.

I have a couple of questions about the power supply.

1. My highest Vf LED is green at 3.3v, but red's Vf is only 2.2v. Since I want to use 5, I would say I need to hook up 16.5 (or even 18v) to V+ on the board. Can the 5v regulator on the board handle that? Is the 18v V+ too high for the string of red LEDs?

2. Do I have to have the same total Vf on each output, or can it vary? Can I have 5 LEDs on one output in series, and only 1 LED on another?

Thanks for any info!

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adafruit_support_rick
 
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Re: TLC5947 LEDs in Series Questions

Post by adafruit_support_rick »

You can drive up to 30VDC to the LED output:
To use: Power V+ with 5-30VDC, and connect ground to the common ground. Then send 3-5V logic SPI data on DIN (data in), CLK (clock) and LAT (latch).
2. Do I have to have the same total Vf on each output, or can it vary? Can I have 5 LEDs on one output in series, and only 1 LED on another?
You can have different numbers of LEDs. The TLC5947 already has a current-limiting resistor, set for about 15mA

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