BBD clock driver info

[d95err]

I have this wild idea of replacing the clock driver chip (e.g MN3102) of an analog delay (e.g the AD3208-project from www.generalguitargadgets.com), with a PIC microcontroller. This would give complete control over the delay time, enabling me to add features such as "Tap Tempo" etc.

However, I've been unable to find any proper datasheets or application notes for the MN3102. The one I found is for the MN3101 which has higher voltage, and the info is very basic.

I would love to know more about this, and analog delays in general. Does anyone have some tips about where to find more info, datasheets or application notes regarding analog delays?  Perhaps there is a "Technology of the BBD delay" article somwhere I haven't found...

[Peter Snowberg]

Welcome to the forum.

I don't have any datasheets, but the information is all very similar. Any clock that gets close but stays within the power rails (such as a PIC I/O pin) will be fine.

BBDs take a two phase clock. One is high with the other is low and vise versa. The timing of the clocks is important. You want to toggle pin states in the same operation to avoid any overlap. Overlap is bad.

I think you've got a fantastic project on your hands. Most of it is just running some counts, doing a little math, and setting a timer.

Here's a BBD datasheet if you don't have one already. http://www.angelfire.com/electronic/autronix/midfielder/zvonimirboban/pdf/MN3007.pdf

[Claus H]

http://www.diystompboxes.com/sboxforum/viewtopic.php?t=25811&

Some info we talked about before..

Claus H

[puretube]

"Give Pics A Chance"  :lol:

[d95err]

Thanks for the info. I'm a software engineer by trade, but not particularly good at the analog stuff. Therefore, the idea to use a microcontroller to control an effect while keeping the sound analog came naturally to me. I haven't worked much with PICs before thogh (although I used to work for a company that develops PIC C compilers...).

I'm going to do some simpler experiments with PICs first before I pursue the BBD project. The one I'm working on right now is to use a small PIC and a digital pot to control the rate of an EasyVibe (a John Hollis design). (Basically a digital version of the LERA project from Geofex).

I'll keep you posted when (if) I make any progress...