I was wondering about flip flop circuits
p.s. working on an xoxo led sign for valentines. running off 110v would the flip flop option be the way to go or is there another less parts way to go about it. I want the x's to blink on when the 0's are off and the O's on when the x's are off. or the first xo then the 2nd xo. not sure yet. also want the "tempo" i.e. the resistor value to be changeable so i can make it faster/ slower
thank you!






























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You can change rate without changing ratio
More C1 to go slower
Less C1 to go faster
Make an Ible about it for us all
Use a 9VDC 150ma Wall Wart
A
However I get the impression you want to use individual ICs
to accomplish this task.
What voltage are you going to use ?
What are the LED voltage and currents for each color ?
What timing is your tempo and range ?
A
would I be able to have them be programmable to different blinking modes or am I limited to one?
Here is a circuit using one 14 pin IC ten Red LEDs for the (X)
and place ten more Red LEDs for the (O)s in place of the green.
A
it it like the current/voltage flows one way then back the way it came to light up the leds in the opposite direction??
that is ingenious.
then R1, R2, charging C1 time later
the green leds turn ON with the red off.
Then R2, C1 discharge time later Repeat...
Look at the pin numbers 1 through 14 <=> that is ONE IC
I set the resistors to 220 ohms for about 20 ma per LED at 9 VDC
and with 5 groups in parallel that is about 100 ma total
which is well below the maximum 300 ma capability
for each IC output stage.
Simply put one set of LEDs in the normal place and the other set of LEDs in place of that resistor. (Keep the circuit symmetrical). It will work exactly as you describe; one set on while the other is off and vice-versa.
I don't like the sound of you trying to use 110v - this sort of circuit should be run off a 9v battery (or 9v power supply).
A micro processor is Way over the top for this and, with the greatest of respect to Steve, I would go so far as to say that a 555 is probably to much too (though I am a great supporter of this chip).
Steve
Steve