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can someone help me to design a blinking LED's which contain 6 branches which has the following numbers of LEDs for each branch:

1st branch = 13 LEDs
2nd branch = 10 LEDs
3rd = 8 LEDs
4th = 12 LEDs
5th = 5 LEDs
6th = 14LEDs

i try to use a astable 555 timer but the intensity of the output of the light are not equal for eacg branches.., attached here is a "livewire" file that i used for simulation.... tnx for response if any..., tnx.., good day

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I don't have Livewire so I can't view the schematic.

You'll get more help if you post the schematic in a format which everyone can read.

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i have a .jpg file here attached..., can u please see it..., i need help badly.., tnx

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Why have you got a battery with the voltage set to 0V wired in series with a 24V battery?

The intensity of the LEDs is not the same because the current flowing through them is different. Google for the formula to calculate the series resistor for the forward current you desire.

The 555 timer has a maximum voltage of 15V to 18V depending on whether it's TTL or CMOS so won't last very long running off 24V. You could use a voltate regulator to power the 555 but that would mean it couldn't switch the PNP transistor off.  There are other circuits which can flash LEDs alternately and can be powered directly off 24V, e.g. an astable multivibrator built from a couple of transistors, see Wikipedia lnk below.
http://en.wikipedia.org/wiki/Astable_multivibrator

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dont mind that 0V battery sir.., its just an error...

one question sir..., can a 9V battery can actually light up the entire LEDs??? or just stick to 24v DC???

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It depends on the 9V battery, a little PP3 battery isn't large enough to provide enough power for very long.

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• 2 months later...

Use a programmable counter (4017/4029), instead of a 555, with an appropriate driver for each branch.
einstein0

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the cd 4017 needs a clock to make it work, could use a 555 for that
gogo

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