It's necessary the SN 74HCT245 IC to shift 3.3v to 5.0v on wemos d1

Archive FastLED Archive
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1

It’s necessary the SN 74HCT245 IC to shift 3.3v to 5.0v on wemos d1 pro on D3 PIN?
I noticed that if i connect a 5 meters strip led with 30/40cm data wire to D3 of wemos all effects are perfect.
If i extend the data wire from 30/40cm to 3/4 meters the strip leds flickeing?
So, i ask, it’s possibile/sure that with a shift level (N 74HCT245) the problem is solved?
I tried the i2c level converter (like in image) but the flickering is the same.
Why?
Thanks a lot

513699f2f9011b42679f6823e3f4ef66.png

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

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Those I2C level shifters have fast fall time but slow rise time. This difference changes the pulse width. For I2C the sequence of pulses matters, but not their width. For WS2812, the data IS the pulse width. This sort of circuit badly corrupts the waveform.

4

Those things are terrible! Use a null pixel or a 74HCT245 for best results

5

What about 74HC245 not 74HCT245?

6

I read somewhere that the T is important, but I can’t remember why or where…

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@Jeremy_Spencer thx