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SOLVED APA102 / SK9822

Discussion in 'Hardware Support' started by sylvaing26, 17 December 2018.

  1. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    Hello everybody,
    sorry for my bad english, i'm a french user of hyperion with my rpi pi 3 B+ with raspbian + kodi.
    I've solder my leds strip (SK9822) for an installation with 151 leds.
    I've a power supply of 5V 10A.
    First, I've my leds flickering. I've brought a level shifter but i've the same problem with this installation :
    [​IMG]

    The flickering disappear when I connect the 5V power with 5V pin of my arduino like that :
    [​IMG]
    My arduino have his own power supply (5V 3A)

    I don't understand the problem.
    I've shop a 74HCT125 but I've not ever receive yet.

    What is the problem ? A poor power supply ?

    Thanks
     
  2. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
    Try disconnecting the 3v+ from the Rpi pin to the shifter. It's not needed.
    level shifters need the input voltage to be the same as the desired output data voltage.

    Hope it helps.
     
  3. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    Ok
    I try this tonight.
    I can also disconnect 5V from Rpi with your option ? (in my secon scheme)
     
  4. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
    It's ok to leave the 5v to the pi.
    However, do not power the Rpi with the usb power at the same time, as the Rpi is now being from the same power supply as the led's.
     
  5. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    Ok,
    but if my pi has also is own alimentation, I disconnect the pi ?
     
  6. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
    Yes. The alimentation of led's will supply the Rpi.
     
  7. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    If I want poweroff my Leds when I don't use ambilight, it's not a good solution.
    This schemes can work ?
    [​IMG]
     
  8. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
  9. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    Hi,
    I've tested the latest scheme I've posted with only 5V or power supply connected, this option doesn't work
    If I connect 3V rpi at the LV input, it work but leds sparking blue and red.
    Do you think the problem is my power supply ? 10A is too low ?
    If I connect at HV the 5V of the power supply + 5V rpi : no sparking...
    I became crazy ! :)
     
  10. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
    It's Ok. Your led's (151) should draw a maximum of around 9 amps (at full white liight)

    I do not have any working experience with the level shifter that you are currently using. So I can't help much currently. When you receive the 74HCT125 I can, as I have working experience with it.

    However, Try this.
    APA102-bb.jpg
     
  11. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
  12. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    Hi,
    thanks for your replies.
    The level shifter does'nt work if 3V is not connected.
    I've measured the voltage in my 4 corners on the led TV, I've seen the voltage is under 5V when most led are lightening.
    I think i'lle wait the 74HCT125 and connect power supply on my 4 led strip...
     
  13. sylvaing26

    sylvaing26 New Member

    Messages:
    15
    Hardware:
    RPi3, +Arduino, +nodeMCU/ESP8266
    Hi,
    with the 74HCT125 leds works like a charm !
     
    • Like Like x 1
  14. Akriss

    Akriss Active Member

    Messages:
    462
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
    Glad you got it working.

    Enjoy!
    :)
     
    • Like Like x 1