WEBVTT

NOTE Neural narration; phrase times estimated within exact synthesized scene segments.

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Start with a low voltage. Use a 5-volt supply, a red

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LED with a modelled 2-volt forward drop, and a target current

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of 10 milliamperes.

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Find the spare voltage. The resistor must drop about 3 volts.

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Divide by 0.01 amperes to get 300 ohms.

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Choose and check. A standard 330-ohm resistor gives roughly 9 milliamperes

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in this simple model. Its power is about 0.027 watts.

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Read the data sheet. Forward voltage varies with current and temperature.

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Check polarity, current rating and resistor power before building.