LED/Frequency question

[[email protected]]

All,

Here is what I want to do, for no other reason than to pracrtice some math design and practical app of theory. Moving from load to power source: I want to group Leds into different strings, each string will have a different cap reac, the same frequemcy will we put into all groups though, the calc of course done so each string discharges and lights at different rate for each th frequency, I would like to use maybe 3 or four different frequencies, spread fairly wide apart, this would make the cap size change in reaction the most managable. The main question is what would be the best thing to use for output of this spectrum of freqs( a hobby budget of course), I know I could use a 555 or 2, something close related for telling the frequencies when to switch, but something to output the freqs has me a little stalled. I have thought about crystal oscillators, VFO, maybe a varactor sort of device. The actual spectrum would depend on the cap calcs(which havn't done yet, which would depend on the frequency spectrum which I havn't sone yet.......ad infinitum) any pros or cons for a particular method would be appreciated

thanks

 

[Harald Kapp]

Welcome

Have you thought about using a microcontroller's output pin? Thus the frequency is easily adjustable in software. You didn't staqte what range of frequencies you have in mind. But considering that it's all about lighting LEDs i assume that the frequencies are well above 100 Hz (to avoid flicker) and below say 10 kHz. This is well within the range a µC can handle.

Regards
Harald

 

[[email protected]]

Thanks for replying, I havn't been able to get into the depth of it yet, I will look into the microcontroller poss, any other helpful suggestions are also welcome. I put a little more on here when I have the oppurtunity to work on tjhe idea, a little