1) Green LEDs generally have a higher Vf than red LEDs. Just one green LED would require a higher trip point to be set.Found this circuit as a replacement for a LM3909. Sounds to good to be true. Could I get away with adding 3 leds to it?
http://pigeonsnest.co.uk/stuff/picprog/single-cell-led-flasher-two-year-battery-life.html
by Aaron Carman
by Jake Hertz
by Jake Hertz
by Jake Hertz