Hi,
I’m trying to control a SK6812 programmable LED strip however, my data line cable is quite long; around 5-10m (I can’t remember exactly). The signal is obviously distorted, as the colours are wrong, and the first pixel is different than the rest.
Looking at the oscilloscope it’s obvious there are signal reflections. Doing some tests with an oscilloscope and a long piece of the same cable showed having a 330 Ω resistor flattened the signal nicely. However, when I inserted it into the signal line, it didn’t help with the LED control at all.
What DOES help is having the 1X probe connected (disconnected from the scope), between the data line and GND. Everything works great. Setting it to 10X REALLY screws things up.
So what is my probe doing to ‘fix’ the signal? How can I replicate this? Can anyone explain more why my 330 Ω resistor didn’t work? Or provide any more information on what is happening and how to fix it?
Thanks.
I’m trying to control a SK6812 programmable LED strip however, my data line cable is quite long; around 5-10m (I can’t remember exactly). The signal is obviously distorted, as the colours are wrong, and the first pixel is different than the rest.
Looking at the oscilloscope it’s obvious there are signal reflections. Doing some tests with an oscilloscope and a long piece of the same cable showed having a 330 Ω resistor flattened the signal nicely. However, when I inserted it into the signal line, it didn’t help with the LED control at all.
What DOES help is having the 1X probe connected (disconnected from the scope), between the data line and GND. Everything works great. Setting it to 10X REALLY screws things up.
So what is my probe doing to ‘fix’ the signal? How can I replicate this? Can anyone explain more why my 330 Ω resistor didn’t work? Or provide any more information on what is happening and how to fix it?
Thanks.