I'm a beginner working on a project which requires flashing high power LEDs, they will be supplied by a battery and flash at a frequency with a 555 timer. However, because I would like the battery to last longer I need to alternate between 3 LEDs with each output of the timer. Currently I have the 555 timer flashing a single LED but I was unsure of how to proceed with alternating between 3 LEDs.
Any help would be appreciated, thanks.
Best Answer
A very common way to do what you want is to have one 555 acting as the oscillator, and drive a CD4017 Johnson counter with it. The counter steps through 10 outputs in series, and you can make a connection such that after three steps it repeats. You will need one driver transistor per LED because the 4017 output is pretty weak.
This type of circuit is called a chaser, and there are many example schematics on the web.