This circuit is an op-amp comparator with three inputs, to compare 3 different voltages and show the higher one by using an LED.
Parts list:
IC CD4001
IC LM324
Resistor 510 ohm (3pcs)
RED LED
GREEN LED
BLUE LED
IC socket 14 pin(2pcs)
Capacitor 220uF
Capacitor 100nF
Circuit:
VCC could be any voltage between 4 to 15V
Video:
