I want to use a WS2814 24V Strip on an ESP32. After i set it up, it started to flicker. After bit of research i found that i have to use a level shifter. So i added a TXS0108E into the circuit. But i still having the same issue. I connected the B side on the 5V and the A side on the 3.3V. The OE pin is connected to the 3.3V with an 1MO resistor. The unused pins on the A side are connected with ground like shown in the documentation. Im hoping that someone is able to help me.
Thanks
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1M may be too high for OE, I just connect it straight to 3.3.
How long’s your line to the first LED? TXS0108 isn’t great and won’t work past maybe 50-100cm or so from my experience.
Also are you sure your 3.3V rail is connected to 3.3V here? Seems connected to EN instead but maybe it’s the photo angle…
Yeah i tried to change the resistor with a wire, still not working. The length of the wire to the rgbw strip is not that long (30cm) but maybe my bad soldering skills could be a problem. The 3.3 V are connected right to the pin. Is there a way to measure if the level shifter is working correctly? I connected the 3.3V on pin 1A for testing and it delivered 5V at pin 2A so it should be good i think. I ordered few 74AHCT125 now and will try that with them.
Static test is simply to set TXS0108E input to GND and see <0.8 V out, then 3.3V in and see 5V out.
Other than that, shorter smaller wires on the proto board are your friend.
Big loops act like antennas, so grounds aren’t and supply wires don’t.
If you can keep the wires to < 3x what they absolutely must be, jumper to GND bus rather than another grounded pin, etc. things will be more reliable. Try and use 22-24AWG wires bent to fit very close to what you need.
Protoboards are for testing, the neater they look, the better the test, even when you get the 74AHCTxxx (which I think is a better choice) Don’t forget the 100nF decouple capacitor.
Thx i wasnt sure if it’s necessary to use the capacitor. Can i use ceramic or Electrolytic capacitors?
TXS0108 is quite weak. You can check your digital signals using an ossciloscope and probably see a bad waveform. My issues were fixed by moving to a stronger shifter like SN74LVC8T245PWR
The 100nF capacitors on the Vcca and Vccb pins are needed to decouple power noise (standard in digiatl ICs) They should be ceramic NOT electrolytic.
Various people have had levels of success with the TXS devices.
The 74AHCTxxx chips are much simpler and effective.
Their biggest downside at the moment (IMO) seems to be the lack of pre-made boards like the TXS devices.
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TXS can be fine. I just ordered some from Amazon for testing and they work. Maybe there are some bad boards out there?
Scope shot that also includes some bad wiring with DuPont jumpers for extra effect. 
The TXS i use were from amazon too. I discovered something interesting. If i connected 1 Strip (3x6 LEDs) directly to the ESP it works fine. As soon i do the TXS between the Strip and the ESP it starts flickering. Tomorrow ill receive the 74AHCT125 Ns and lets see if they will work.
What are all those power (looking) cables hooked up to?
The breadboard is NOT the correct place to do power distribution, it’s suitable for data testing only.
You’re much better off to do a single power wire from the breadboard to the power supply for the ESP and shifter. Make all the other power connections for the LEDs directly to the power supply using WAGO connectors, or terminal strips or even wire nuts. You won’t get reliable currents through a breadboard.
Definitely cleaner (pretty good) than the 1st pic. But get the LED power off the breadboard.
Ok ill do that tomorrow, the many power cables are because i get 24V from the power supply (for the led strips) and then i go into a voltage converter that transforms it into 5V for the ESP. If you mean the Y(st)Y wires at the left, that are all the wires (less than 1m) to the LED strips. My plan was to wire up 8 strips but dont worry, every strip has a length of 3x6 LEDs.
Thx for helping the problem was the shifter. With the 74AHCT125 N it’s working, even with 4 channels.
Glad to hear you’re up and running - now the fun begins 
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Not for y’all, but for average folk passing by that fought flickering issues on the WS2814 24v, get a DigiQuad like I did that just works. Great quality & compact board.