Some daze, like yesterday, you can’t see the forest for the trees.
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This morning after a good night’s rest I set up a simple test circuit with a 1K resistor and the 10mm white LED. The power supply was my power car with a TE and A-C Lithium-Ion battery. The input voltage to the circuit was 22.5 volts.
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Voltage Supplied â€" Voltage of the Device (LED) / Maximum Current for the Device (LED) = Resistor Required
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22.5 Volts â€" 3.6 Volts / 0.020 amps = ? Ohms
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18.9 Volts / .020 Amps = 945 Ohms
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Hooked up the circuit with a 1K just like before and the LED didn’t light until the TE was at full throttle. Well ya dummy, full throttle voltage was what you used to calculate the resistor. DUH! Give you head a shake, you brain is stuck.
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So maybe a 5 volt voltage regulator and a 100 ohm resistor (5.0 â€" 3.6 / .020 = 75) would provide constant lighting. A diode on the positive input leg of the voltage regulator would prevent magic smoke when the current was reversed and provide directional lighting. Correct?
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But what do I do with my Christmas (red/green LED classification) lights? If I add them to a parallel branch, they will only light one way?
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Sound of grinding gears heard, temperature rising, smoke begins to waft ……… I need a constant voltage supply for all the devices? The battery! But how can I get directional lighting if I use the battery?
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My head hurts! Time for lunch!