I would like to build a circuit to control 4 LEDs via an inducted current. I would like the inducted current to provide the power for the LEDs, however I would like the LEDs to be lit in a certain arrangement depending on the current. That is I would like a certain signal to correspond to a a portion of the LEDs to be lit at a certain intensity. I would like to have relatively high granularity to control each LED (at least on a percentage level / 0-100 with steps of 1). What is the simplest circuit I could use to do this from primitive parts (gates, diodes, capacitors, etc...) not ICs or anything complex? Any suggestions would be highly appreciated.

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  • Can I ask why? Controlling LEDs is a simple task but you have added lots of complexity. – MIL-SPEC Jul 18 at 10:16
  • Voltage is induced not current. Current flows as a result of induced voltage and a load. – Andy aka Jul 18 at 10:51
  • The question as it stands is pretty vague. Critical parameters include the voltage and current at the transformer secondary. Everywhere you write "a certain..." you should be more specific. Explain why you can use "gates" but not "ICs". – Elliot Alderson Jul 18 at 11:22
  • Hi thank you all for taking the time to comment. So sorry about the vagueness. I'm a software developer by trade and just starting to learn about electrical engineering. I would like to use simple circuitry because I need this to be really miniaturized. One idea I had was to use high pass / low pass filters to do this if a circuit would be to complex to make from primitives. The use case for this is a light without a battery that lights up in a specific arrangement when near the induction source. – Anters Bear Jul 18 at 14:28
  • A "simple circuitry" solution will likely be larger than a solution that makes good use of ICs. The whole point of ICs is to integrate the solution into a smaller and more efficient form-factor. – Daniel Jul 18 at 15:00

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