WS2813 and SK6822 dual signal , both of the signal is data , why 2 data signal?, it is for led strip one led is broken,another data still can work ,unless 2 next led Two successive LED is broken then the led strip can not working .
which can make the led strip one is broken will not affect another led working ,but the frequency speed WS2813 is much better than WS2812B . it is much better than ws2812b and sk6812, and when WS2813 VS WS2812B ,you can think WS2813 LED is ws2812b updated version , and SK6822 is sk6812 updated version , but we can see the difference from the led strip picture between the WS2813 AND and sk6822, You can see the SK6822 LED strip have led chip and capacitors in the led strip , but WS2813 LED strip only have led chip on the surface of led strip , this is Becasue WS2813 led chip not only have the ic ,but also capacitors package in 5050.
by the way ,When i compare the datasheets WS2813 and SK6822 , The SK6822 specs mention ESD pressure (ElectroStatic Discharge), but WS2813 does not., so i can not make sure WS2813 have it or not. but WS2813 is really very good as the Capacitors is packaged in 5050, and have much faster frequency speed than WS2812B.