Due -> TXB0108 LLC -> NeoPixel

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Jaketeck
 
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Due -> TXB0108 LLC -> NeoPixel

Post by Jaketeck »

Still very new at this stuff. Did quite a bit of searching but could not find an answer I fully understood.

I've been using an Arduino Mega but recently upgraded to the Due to get a bit more processing power. This is when I discovered the 3.3v output just does not work well with the NeoPixel. I picked up the TXB0108 board https://www.adafruit.com/product/395 to solve the problem but wanted to make sure I had it connected correctly before firing everything back up.

Due 3.3v -> VCCA TXB
Due 5v -> VCCB TXB
Due GND -> GND TXB
Due Pin 6 -> 400 OHM Resistor -> A1 TXB
B1 TXB -> DIN Neopixel WS2812B

Should I also be running a connection between OE TXB and 3.3 VCCA TXB?
I'm using external power for my NeoPixel strips. Should I be connecting its GND to the TXB as well? I've been connecting the external power supply's GND to the Arduino. Is this a good practice?

I have read that the TXB's output is fairly weak. I was planning to connect a single NeoPixel directly after the TXB to be able to run a longer length of cable to my first set of LEDs. What type of distance have people be able to run between NeoPixels?

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adafruit_support_rick
 
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Re: Due -> TXB0108 LLC -> NeoPixel

Post by adafruit_support_rick »

Jaketeck wrote:Should I also be running a connection between OE TXB and 3.3 VCCA TXB?
Yes
Jaketeck wrote:Should I be connecting its GND to the TXB as well? I've been connecting the external power supply's GND to the Arduino. Is this a good practice?
Yes. The common ground is required.
Jaketeck wrote:What type of distance have people be able to run between NeoPixels?
A couple of meters should be OK.

Jaketeck
 
Posts: 2
Joined: Sat Jul 12, 2014 1:28 am

Re: Due -> TXB0108 LLC -> NeoPixel

Post by Jaketeck »

Cool! Thanks!

I got a little impatient last night and tried it out without connecting the OE. Seemed to work great. I assume using the OE correctly will give me more stability?

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adafruit_support_rick
 
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Re: Due -> TXB0108 LLC -> NeoPixel

Post by adafruit_support_rick »

Should be more stable, yes.

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