I'm trying to drive a WS2811 strip with the TXB0104 from the ESP8266 however

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I’m trying to drive a WS2811 strip with the TXB0104 from the ESP8266 however the TXB0104 doesn’t seem to do its job of high speed level shifting…
On the 3.3V side I can drive the strip almost fine (few glitches) but as soon as I put it on on the 5V side it starts blinking randomly…

Here is the Fritzing of the project. Let me know if I did something wrong or if the TXB0104 doesn’t meet the requirements (tried 2 different to be sure…)

Thanks!

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@Antoine_Bertin - You should read the following post on this community:

https://plus.google.com/114379680414588835320/posts/BQS8DLUPXyQ

Especially important is Jeremy Spencer’s comment showing the following article on level shifters:

http://happyinmotion.com/?p=1247

You need to use a 74HCT245 or a 74AHCT125 level shifter as per the happyinmotion post and as per common practice here on this community. Also, unused pins on a level shifter should be grounded. I use the 74AHCT125 level shifter with my Wemos D1 Mini Pro and with my various Teensy MCUs along with a 5 volt power supply.

Finally, you should put a despiking capacitor across the V+ and ground of your power input feed.

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Thanks for your answer, meanwhile I made various attempts to make it work and it finally did when I replaced the LED strip by another one with a shorter cable (first LED was 1.5 meter away).

I think it may have something to do with the signal out of the TXB0104 being very weak (couldn’t even read 5V out of my multimeter).

On which side should I ground the unused pins of the level shifter? I don’t think that matters but I’d like to know the best practice for that.

Also I’ve added a 1000uF 6.3V capacitor near the LED strip.

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@Antoine_Bertin - Glad to hear that you got things working.

I have had strip problems when using a level shifter with a long cable run.

I believe that you cannot measure the data in or data out voltage with a multimeter but you need to use an oscilloscope.

As to the ground question, you have to ground all unused pins on the level shifter. I am not sure what you mean by which side to ground?