Help with Hi-Striker!! (Scaled LED cascade)

[dr.reddog]

First time poster; hopefully someone can help me out. I'm trying to build a circuit for a LED Hi-Striker. This is my inspiration [url]http://jmillerid.com/wordpress/tag/hi-striker/[/url]

I would really like to generate this result without having to resort to Arduino because I want to do this on the super cheap (I hope to build several for a children's fair in my neighborhood). I don't care about the sounds or flames, I just want a vertical LED cascade that responds to a scaled analog input.

Thanks for any help!!

[admin]

If you need lots of LEDs (>10) then your best bet would be a microcontroller. Atleast you could have someone do it for you. It would ease the construction greatly.

If you can live with less LEDs (<=10) then there are chips which do this. Here are some links:

http://www.national.com/ds/LM/LM3914.pdf
(read the application hints section on how to expand to more LEDs)

http://www.stefanv.com/electronics/esv.html

[dr.reddog]

Thank you! This is exactly what I needed! I think what I might try to do is build the circuit with 30 LEDs, but have three LEDs per output. That way the array is larger, but there will only really be 10 'stages'.

[dr.reddog]

I realize this chip is a display driver, but would there be a way to connect an electric buzzer to the 10th output pin? I would like to have a buzzer ring (or something else fancy happen) when the scale max's out (ie; 'you win!'). Thanks.