I’ve got the appropriate amount of light for my microscope ring light, but now I need to put it all in an enclosure of some sort.

If I don’t have a custom board to solder these to, what are my best options for connecting these she mounting them into something?

If this is too vague, please let me know if I can clarify

  • marcos@lemmy.world
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    4 months ago

    Not only you always need at least a resistor, but matching the power supply voltage to the leds drop will ensure you’ll have a hard time maintaining their brightness on the real world.

    If you want to keep it simple, leave 1V or 2V as a margin and add a resistor to get the desired current. If you want to make it fancy, get a led driver.

    • sneekee_snek_17@lemmy.worldOP
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      4 months ago

      That being said, I redid it with your input in mind. It’s currently got 100U resistors and draws a good bit more than the power supply is capable of

    • sneekee_snek_17@lemmy.worldOP
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      4 months ago

      When you say “the real world” what do you mean, exactly? Because the 12V, 200mA power supply I used to power it for these pictures is likely what will ultimately power it

      • coffeejoe@lemmy.dbzer0.com
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        4 months ago

        You have a current limiting power supply. So the power supply transistor is acting as the resistor for you in this scenario.

      • marcos@lemmy.world
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        4 months ago

        For example, as the leds on the original circuit age, you can expect a few of those lines to stop getting any current, and the others to get brighter and brighter until they fail.

        That can happen very quickly too, if their temperature varies a lot (how much is a lot depends on the leds). Or if you change your power supply for one capable of more current, it’s likely that everything will just fail immediately. Or, if you have a noisy one, you may severely reduce the leds lifetime.

        As a rule, you can’t use diodes internal resistance as a power limiter. It does not behave the same way as resistors and will surprise you on every bad way possible.

        • sneekee_snek_17@lemmy.worldOP
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          4 months ago

          Huh, if I had the time I’d do some reading about it. Sounds like there’s some really interesting physics going on there