Hello, I have a WS2814 RGB strip for 24V and a 24V power supply. I am using a 3.3V Arduino board that will be powered separately.
I am now wondering how to connect the 24V RGB strip to the Arduino. Most online resources only show how to use 5V strips, which makes things easier.
When the SPI voltage is 24V, is the voltage of the data pin also required to be 24V or is it fine to drive it using 3.3V?
I have seen the need to connect the ground of the board with ground of the power supply. Is this also the case when using differing voltages and separate power supplies for board & LEDs?
Furthermore, the data pin for SPI seems to usually be connected with a resistor. How is its value calculated?
So it depends on the supply voltage of the WS2814 driver chips. The LED strip specifications should include information on this, and/or the logic level input voltage.
This is definitely far beyond the maximum ratings of the driver chip.
What is "SPI voltage"?
SPI = Serial Programming Interface. The 24V you refer to is the strip power supply voltage. I wouldn't call that "SPI", but maybe you mean something else?
Correct.
Yes. The Arduino and LED strip need to reference to the same GND level, so GND needs to be connected.
It's generally not very critical and something like 100R or so. A fairly low value is used to ensure clean logic level transitions, while at the same time reducing peak currents.
