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100 LED's

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New Member
I am new to electronics and need away to control 100 Ultra bright LED's (200 would be better). I want to be able to have 5 different paterns wich can be selected using a button and I also want to be able to control the speed of the effects.

How would I go about doing this.

Mr Thick! :shock:


New Member
Depends upon required pattern and display configuration
A quick and simple solution is to use a small pattern that can be repeated with mutiple smaller display modules


Just a suggestion. :idea: You may use LED's in a matrix format. The rows could be run by two LM3914's and the clock signal could be obtained from a single 555. Of course there are other various formats you may employ.


New Member
Ok, how about controlling 100 leds to do:

Always on (Normal)

Running light (LED's must all be on except for two that produce the running effect.

I would like to control speed if possible.

Would this be easier to do???



New Member
ok. why would a LM3914 be used here? this is a VU meter circuit.
what you need is a counter.
if you want to have 100 running leds, 2 at a time then that means you only need to count to 50.
do you want to have them count from one direction, or go from one end to another, then reverse?
the simplest way you could do is to have them count in only one direction.
all you need for this is a 555, 2 4017 counters, and 5(or 10 if you want the leds to turn on one at a time) BC547 transistors and some descrete components.
the leds need to be wired intro a matrix.


New Member
I need it so that there are three modes:
1. Off
2. All LED's ON
3. All on, but with a sequence that turns two LED's off, one after the other (I have tried to show below)

off | off | on | on | on | on | on.....
on | off | off | on | on | on | on.....
on | on | off | off | on | on | on.....
on | on | on | off | off | on | on.....

Does anyone have any circuit diagrams fo this??

Thank you
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