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Engineering4 min read

Reading a circuit diagram

Symbols, loops and the one rule that makes it click.

A circuit diagram is a map of loops, not a picture of the board. Wire length means nothing; the connections mean everything.

Current needs a complete loop from the source, through components, back to the source. If you can't trace the loop with a finger, the circuit does not work.

Series means one path (current shared, voltage split). Parallel means branches (voltage shared, current split).

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