Simple LED Fader?

[username 198]

So... i've always wanted to make a pretty LED Fader and be able to implement then on my circuits.

 

By LED fader I mean this:

 

Now you could acourse use the launchpad but with a 16Mhz MCU I would think i'd be a waste of IO and processing power. Consequently i've been trying to look for a simple hardware alternative. I created this circuit this weekend that uses a single supply lm358. Works like a charm but still requires alot of components. Does anyone know of an IC that is specifically meant for this? I search digikey for led driver and only get about 20k results. I supppose I might be able to mimize the components if I use a 555 timmer?

 

[Fe2o3Fish 33]

"normally", the LP runs at 1-MHz but, honestly (and hopefully the MSP gods won't zap me), you'd be better

off with an Atmel Tiny13 (8-pins) or one of the newer ATTiny9 (6-pins but no DIP package). You'd wind up

with far fewer components and it runs about the same speed sans crystal. It's a shame that TI doesn't

make an 8-pin '430.

 

-Rusty-

[username 198]

Thanks for the reply. A micro is a decent idea. However, the cheapest AT Tiny is like 1usd on digikey which would be alot more then a cheap smt lm358 + smt resistors. Not sure I would want to implement that. Is there by chance a cheap IC that will do this?

[Fe2o3Fish 33]

I sincerely doubt that there's a pre-programmed/wired chip that will do this.

Programming a small controller is fairly trivial since I've already dropped the

code for this, right here (albeit for the '430).

 

If you're THAT worried about cost, are you planning to make a bazillion of them???

 

-Rusty-

[oPossum 1,083]

I would use a PIC10F200. Cheap and versatile.

 

I can't think of an analog circuit much simpler than what you posted. This is the best I could do...

 

 

http://www.falstad.com/circuit/#%24+1+5 ... 25+1+-1%0A