How do connect LED SK6812 to 3.3 logic?

Hello,

I create my board controller, with base in ESP32. ESP32 works in 3.3V logic, this is Arduino Pro Micro.
I have a small LED light strip consisting of 9 LED SK6812. I plan to use it with ESP12. From a board to a tape about meter of a wire. In the power line => 5 V, logic => 3.3 V.
I read that 3.3V is a small logical voltage for SK6812 or WS1282. This can lead to failures in the management of LEDs.

I found the level shift boards: SN74AHCT125DR (TI) / TXB0108PWR (TI) / TXB0102DCUR (TI).

The question is whether I should spend space on the board to shift the level if I have only 9 LEDs? Or count does not matter?

You are correct, the count of LEDs does not matter. Even with one led, the 3.3V signal may not work. But if the first led can receive the data, it will transmit the data to the next led at the correct level. Your 74hct125 idea should work.

PaulRB,

Thank you!!!

Then I will connect using 74hct125.
I apologize for the off-topic question.
Can I use free outputs of this chip to control transistors? Just transistors also require a voltage of 5 V at the base.

Suyano:
Can I use free outputs of this chip to control transistors? Just transistors also require a voltage of 5 V at the base.

What kind of transistor? Can you post model number or a link please. You used the word "base" and that implies BJT, not FET. With BJT, the transistor is switched by current, not by voltage, so 3.3V would work as well as 5V if you use an appropriate resistor. If your transistors are FET, for example MOSFET, then they could either be logic-level, in which case 3.3V may be enough, or non-logic-level, in which case 5V will not be enough.

Suyano:
Then I will connect using 74hct125.

Mind you, a 74HCT14 will do just as well - and may be more readily available/ cheaper.

PaulRB:
What kind of transistor? Can you post model number or a link please. You used the word "base" and that implies BJT, not FET. With BJT, the transistor is switched by current, not by voltage, so 3.3V would work as well as 5V if you use an appropriate resistor. If your transistors are FET, for example MOSFET, then they could either be logic-level, in which case 3.3V may be enough, or non-logic-level, in which case 5V will not be enough.

Transistor BC337-16 - https://www.mouser.com/ds/2/395/BC337-16%20Series_B14-521022.pdf

Paul__B:
Mind you, a 74HCT14 will do just as well - and may be more readily available/ cheaper.

Thank you!

Suyano:
Transistor BC337-16

BC337 is a BJT (base-junction transistor), it does not need 5V to switch, it will switch fine at 3.3V provided you choose an appropriate base resistor, a lower value than you would use with 5V. There will be no advantage to driving it through the 74HCT chip, because the ESP output pin can supply up to 40mA, but the 74HCT pin can supply only 35mA.