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Wiring Help. Neopixel connected to a reversible 3 pin connec
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Wiring Help. Neopixel connected to a reversible 3 pin connec

by wassabi on Wed Jun 23, 2021 12:26 pm

I found these really cool 3 pin magnetic connectors and want to use them to connect to WS2812B neopixels. Problem is that the connectors are not keyed and could be plugged in backwards.

Some basic info here: https://electronics.stackexchange.com/q ... ors-called

Which wiring combo should be safe for wiring to a neopixel? I have read that the WS2812B have reverse voltage protection, but I don't want to trust that.

Code: Select all | TOGGLE FULL SIZE
   FWD  REV
1  VCC  GND
2  DATA DATA
3  GND  VCC
KABOOM?

Code: Select all | TOGGLE FULL SIZE
   FWD  REV
1  DATA GND
2  VCC  VCC
3  GND  DATA
OK?

Code: Select all | TOGGLE FULL SIZE
   FWD  REV
1  DATA VCC
2  GND  GND
3  VCC  DATA
OK?

wassabi
 
Posts: 6
Joined: Fri Jun 22, 2012 10:30 am

Re: Wiring Help. Neopixel connected to a reversible 3 pin co

by adafruit_support_bill on Wed Jun 23, 2021 8:15 pm

I have read that the WS2812B have reverse voltage protection,

They do not.

The chip specs say that you should not connect the DATA signal to anything less than GND or greater than VCC. I don't believe that there are any safe reversible combinations that would guarantee that.

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Joined: Sat Feb 07, 2009 10:11 am

Re: Wiring Help. Neopixel connected to a reversible 3 pin co

by wassabi on Thu Jun 24, 2021 8:24 am

In that case. How about a resistor on the data pin, so the neopixel won’t be inadvertently powered by a data connected to ground.

The data sheet says 1 µA for the max current draw of the data pin. So I am thinking a 100k to 1M ohm.

wassabi
 
Posts: 6
Joined: Fri Jun 22, 2012 10:30 am

Re: Wiring Help. Neopixel connected to a reversible 3 pin co

by adafruit_support_bill on Thu Jun 24, 2021 3:38 pm

You can try that to see if it works. For longer runs we recommend something in the 300-500 ohm range as a termination resistor for longer runs.

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Joined: Sat Feb 07, 2009 10:11 am

Please be positive and constructive with your questions and comments.