1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

RPi + Other Software level shifter aternatives

Discussion in 'Hardware Support' started by Refthoom, 30 August 2020.

  1. Refthoom

    Refthoom New Member

    Messages:
    14
    Hardware:
    RPi3
    Just wanted to mention here that as an alternative to the level shifters sold under that name on banggood and aliexpress, you can apply TTL ic's like below. I have tested these on my setup Rpi 3B+ on HyperBian alpha7 with WS2815. The advantage of these buffers over the level shifters is speed and they have built in logic to keep the signal clean.

    - Quad buffer SN74AHCT125N
    The Rpi output is connected to the input, the Output Enable connected tp GND. The output is connected to the LED strip data line.

    - Quad AND gate SN74HCT08
    The rpi output is connected to one of the AND gate inputs, the other input is connected to VCC (5V), the output is connected to the LED strip data line.

    I also use 1k resistors on all input and output lines as a precaution to spikes and shorts.
     
    Last edited: 17 October 2020
  2. akhak

    akhak New Member

    Messages:
    15
    Hardware:
    RPi3
    Hi! What settings have been made for selecting the feed?
     
  3. Refthoom

    Refthoom New Member

    Messages:
    14
    Hardware:
    RPi3
    Not sure what you mean by that. This topic is only about hardware, specifically level shifting from 3.3V to 5.0V, so no settings are involved.
     
  4. akhak

    akhak New Member

    Messages:
    15
    Hardware:
    RPi3
    I'm very sorry then.. Just wanted to ask how to connect ws2815 and what to set the HyperBian alpha7 settings. I also have ws2815, but HyperBian does not have it on the SPI bus. In any case, thank you!
     
  5. Refthoom

    Refthoom New Member

    Messages:
    14
    Hardware:
    RPi3
    No worries, just wasn't clear what your question was.
    Hyperion settings for WS2815 is the same as WS2812.
     
  6. akhak

    akhak New Member

    Messages:
    15
    Hardware:
    RPi3
    Yes, thank you very much, I found on the Internet that I have to connect the B tire to the GND, then the tape will work as 2812.:thumbsup:
    thank you very much;)