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Bicolor led

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Solardave

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Hi,
I'm a relative newbie but I've constructed a solar powered lipoly charger tied to a minty boost. The charger has 2 status pins for LEDs to indicate charging and then charge complete. When charging s1 is high and s2 low. When charge is complete, s2 goes high. I'm looking for a way to use a bi-color red/green led to indicate charge status as opposed to using 2 LEDs. Any help on this would be greatly appreciated.
 
Welcome to ETO, Solardave!
I would use a three-pin common-cathode LED. Just connect the two cathode "sockets" on your circuit together, and each anode goes to its respective "socket." Let me know if this doesn't make sense. I'll see if I can draw a picture for you. :)
I hope this helps!
Der Strom
 
Thanks for the reply. I am using a cc bicolor led. The problem is that s1 stays high after the charger reaches fully charged and then s2 goes high as well. Using a cc bicolor led won't get me from red to green but gives me sort of an orange so I guess I'm looking for a circuit that will normally light the led green since s1 will be high during charge and then sense S2 going high when charge is complete and cut s1 out of the circuit allowing the other anode on the led to switch from red to green. If all that makes sense.
 
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Because of the way the "die" is doped (the part of the LED that gives off light), It would be difficult to have something "normally light green," if I am understanding you correctly. Perhaps you want a zener diode or perhaps even an inverter to sense when s2 is on, and switch off s1. I think this would be a much easier way to do it.
Der Strom
 
Are you willing to add some additional circuitry, including a transistor, diode and some resistors, or possibly a 14pin DIP to save having two LEDs. Thats what it is going to take...
 
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