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Submitted by James-Stark on Tue, 2013-08-20 16:18


So the answer to this question is probably painfully simple, but it's beyond me, so I have to ask:

I have a coworker that is really into model trains. He's trying to build a little status indicator circuit that will light up one of two LEDs depending on the polarity of the track (forward/reverse). He tells me that depending on the speed desired, the voltage can range from 12v-24v, but is usually around 18v. So my thought was to design a small board that diverts some power to a 5v regulator, passes that through a rectifier to match the polarity to the LED...but then how do I create the logic to decide which bulb to illuminate? Is there a simple little IC that could do that?



James Stark

Submitted by Twelvizm on Tue, 2013-11-26 15:29


I have a project that I'm working on that involves LED lights, a power source, and a specific manner of delivering the power similar to the Apple Magsafe connectors.