Using a bulb as an LED resistor.

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Joined: 05/31/2014 - 15:32
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Using a bulb as an LED resistor.

When I started out in this a white LED bulb was $4 and only drew 50 milliamps. So I was never able to get enough of them together to try this. The simplest LED circuit uses a resistor to limit current. While this is inefficient it is also more reliable. It will work with a bit of water in the system. The resistor generates nothing but heat which is generally wasted. Why not use an incandescent bulb as a resistor? Now I can do the math I know a flashlight bulb produces only 10 lumens per watt. Still that’s my power and I don’t want to waste it.

Last seen: 5 days 6 hours ago
Joined: 02/25/2016 - 17:38
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Location: Uruguay

A 8×7135 (2.8A)linear driver with a nichia 219C (low vf) led would dissipate about 1V = 2.8W in the worst case. Is there a reliable enough incandescent bulb that will work at 2.8W?