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blinking a LED

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i am monster

New Member
useing a 555 timer you can make a LED blink and by changing R2 you can change the speed it blinks
then you can add more LEDs in series that all blink at the same speed..

but what if i want to have two LEDs using the same 555 curcuit blink on different speeds?
how would i do that? or would there just have to be two of the curcuits to make two leds blink at differnt times?
thanks for any help:)



Well-Known Member
Afraid you're going to need two 555's to get them to blink at two different speeds.

You can buy a blinking LED, that might be easier for the other one.


Well-Known Member
you can have them blink alternately

one when output goes high and second one when output goes low.
just insert an LED and resistor between power and output pin.
some great 555/556 circuits
LM555 Timer Circuits
or a calculator
555 Calculator
if you want to use just one chip then a 556 is doable
a 558 if you want 4-555's in one.


Well-Known Member
what is the 555 / LEDS for?

if you really want to go big time go with a PIC
then you can get say 8-16 LEDs blinking at different speeds
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