EEVblog Electronics Community Forum

Electronics => Projects, Designs, and Technical Stuff => Topic started by: John Anderson on August 18, 2016, 07:38:28 am

Title: Bicolor LED connected series/cascade
Post by: John Anderson on August 18, 2016, 07:38:28 am

Hi,

I was wondering if exists a commercial bicolor, 3-lead LED with internal connection of the 2 LEDs in series/cascade, so by having connected the 'extreme' leads to +Vcc and Gnd, and applying a digital signal to the common lead, the LED directly lights up accordingly to the signal without the need of any external circuitry rather than the limiting resistor.

Thank you!

Title: Re: Bicolor LED connected series/cascade
Post by: ludzinc on August 18, 2016, 08:59:10 am

A common anode Red / Green LED will work for you here.

Use the one resistor on the anode, wire the green to ground. Wire the red to your signal pin.

When the signal is high, Green will light. When low, Red will light (due to lower voltage drop across Red LED).