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  1. #1
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    LTspice model for COB LED

    Hi,
    Do you know how I can get a LTspice model for the LC019D and LC033D LEDs from Samsung?
    Ie something that gives the same I,V curve when a DC sweep is done?
    (pages 26,27 of datasheet)
    https://cdn.samsung.com/led/file/res....3_Rev.2.3.pdf


    (I am aware of using the "n" parameter to put LEDS in series)

    I did the attached but its not accurate

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    Re: LTspice model for COB LED

    The graph shows the LC019D conducting 1A at 37V.
    Starting out with a simulation, I changed the led to that spec, but it makes the curve too steep (because the led equation is exponential). However by combining a series resistor, it makes the slope more linear and more gradual. I used trial-and-error. because it's not obvious how to derive an equation from the curve.

    Click image for larger version. 

Name:	led 33V plus series 4 ohm resistor resemble hi-V led.png 
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    The led conducts 1A @33V. The 4.4 ohm resistor adds another 4.4V @1A.
    Over a range of 31 to 39V, current draw goes from 94mA to 1.3A. The curves are similar.


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