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  1. #1
    1000+ Poster - Fantastic Contributor Jackpilot's Avatar
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    digit display voltage

    What is the MAXIMUM VOLTAGE to feed into these yellow displays.
    (MAN3840A)

    Right now, to be on the safe side, I use 3V, which give me the brightness I want, but I'd like to feed regular 5V with a resistor


    Jackpilot
    B737-700 Posky
    FS9/P.Magenta
    without PMSystem

  2. #2
    2000+ Poster - Never Leaves the Sim Trevor Hale's Avatar
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    Treat each segment as it's own LED.. If you can do it with an LED then you can do it with the 7 Segment display.

    Trev
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  3. #3
    1000+ Poster - Fantastic Contributor Jackpilot's Avatar
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    Does it mean that I have to put a resistor at each segment (10 digitsX7=70 resistors?)
    Jackpilot
    B737-700 Posky
    FS9/P.Magenta
    without PMSystem

  4. #4
    500+ This must be a daytime job
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    Hello Jack

    I think that you may be able to use a higher supply voltage and only one resistor dependent on the voltage drop and current drain for each segment. If the segments act like a typical led ie 2volt drop and 20 ma drain then you should be able to feed 32 segments with one 100ohm resistor - see this link

    http://ledcalc.com/

    I would wait for confirmation from others though first!!

    Regards

    David

  5. #5
    150+ Forum Groupie Kerbo's Avatar
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    Quote Originally Posted by Jackpilot View Post
    Does it mean that I have to put a resistor at each segment (10 digitsX7=70 resistors?)
    If you want all of the segments to have a consistent brightness, then yes. When you use a common resistor for all segments then the current draw changes with how many segments are lit. This change in brightness may or may not be enough to bother you.

    What kind of circuit/controller are you using to drive the displays?
    Kerbo on YouTube or Twitch
    github.com/wriley

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