WS2812D signal question

Other Hardware General Electronics
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I am driving a WS2812D (file at JLCPCB) chain from an Arduino output. The chain is a typical series arrangement, think of it as ABCDE. ABC are at a location 1 m from the Arduino. DE are at another, 2 meters distant from ABC. I have the necessary bulk capacitance, local capacitance, and series resistances all as specified by the manufacturer.
I would like to duplicate the appearance of C(call it C') at the start of DE. Effectively, the appearance then would be ABC ---- C'DE.
To do this, I would split the signal output from B, routing it to the input of C on the ABC panel, and the input of C' on the C'DE panel.

What should I do about the series resistance at C on ABC, and at C' on CDE; if I leave them both as 75 ohms, that seems to me to significantly overload the output of B; looking at the WS2812D Spec, it's not very clear what the capability of the WS2812 output might be.
Schematic, for those who need it:

LEDs
LEDs1461×707 6.23 KB

No, I didn't show power connections. Power to the LEDs is an external supply, with ground commoned to the Arduino as per best practices.
For clarity, imagine the LEDs shown are labeled ABC C'DE

I would just wire it up and try it, but I thought I'd ask first. Any suggestions?

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No it does not. It is a series resistor, and the input it leads to is very much higher impedance. And electrically, if anything, adding a resistor reduces the load on the output, which output can certainly drive two inputs.

I'll take a look at the datasheet to see what might be alarming.

TBH since there are no resistors between pixels on a strip, it never would have occurred to me to use any downstream to the first one that eveyone insists be used.

I read somewhere that the habit started with the original smart LED that had some inferior input circuitry. Somewhere, the internet you know. I never used any until I saw the best practices write up at Adafruit, now I use one.

YMMV.

a7

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More than one "source" says to add the resistor if the pixels are more than 10 cm apart. It has to do with waveform shaping/reflection suppression. Effectively it does act as a load, if we're talking about impedance matching at high frequency. But details are scarce from WS, so we're left with interpretations by others, such as Ada.
Guess I'll just go ahead with the default.

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