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I have connected 75 WS2812B LEDs in parallel circuit as shown in manufacturer's datasheet: Source: https://www.tme.eu/Document/64e8d425b90f84990264129a9679149c/WS2812B-V5.pdf Source: https://www.tme.eu/Document/64e8d425b90f84990264129a9679149c/WS2812B-V5.pdf

Since all LEDs should emit the same color, it worries me that two of them are more bluish than they should be (see picture below). Is it possible that absence of current limiting resistors can cause such a problem? I connected LEDs to 5 V power supply, so I decided that there is no need to place additional resistor (since these LEDs can operate at 5V). Also, no resistors are seen in manufacturers circuit diagram.

enter image description here

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    \$\begingroup\$ These are not raw LEDs, but combo ICs and LED circuits which have built-in current limiting. You would never use current-limiting resistors with these. \$\endgroup\$
    – DoxyLover
    Commented Oct 7, 2023 at 13:19
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    \$\begingroup\$ It's far more likely that you haven't same the same instruction to each LED than for them to be so different by themselves. \$\endgroup\$
    – brhans
    Commented Oct 7, 2023 at 14:08
  • \$\begingroup\$ Read the data sheet and look at the brightness table (min and max)? \$\endgroup\$
    – Andy aka
    Commented Oct 7, 2023 at 14:13
  • \$\begingroup\$ Do they come from the same batch? What’s the guaranteed color accuracy from the datasheet? \$\endgroup\$
    – winny
    Commented Oct 7, 2023 at 14:23
  • \$\begingroup\$ @Tomass, it's been my experience working with LED manufacturers some years ago that their CIE hue varies enough to be easily noticed even when driven by precision current sources, and even amongst dice cut from the same wafer. Systems incorporating many in a display system where emitter-to-adjacent-emitter hue is important must be calibrated. I've written software that does exactly that using matrix methods on measurements made with a spectro-photometer. I'm not at all surprised by your results. \$\endgroup\$
    – periblepsis
    Commented Oct 7, 2023 at 20:30

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