Simplest way to propagate a digital pulse?

Hi All,

I want to propagate a digital pulse down a line of maybe 100 modules,
each separated by three inches or so. I want to apply a pulse to the first
module which will turn on and do its thing, then as it turns off, pass the
pulse to the next module, etc., etc.

Currently, each module has a D flip-flop with the propagating pulse on
each module's D input (Q out from the previous module), and a separate,
common clock line going to all the modules. As you can imagine, I'd really
like to not have to drive a 25 foot clock line with a 100 device fan out.

Of course, I could buffer it on each module, but I'd much rather be rid
of the clock line all together.

Each module needs to stay on for the same amount of time, though I'd
like to be able to adjust this, perhaps by varying the width of the applied
pulse. Of course, without a separate clock, I don't see how to accomplish
this.

This seems like the sort of thing that would have been solved already,
but I'm not finding what solutions might exist. Can anyone enlighten me at
all?

Thanks,
Max
.

Relevant Pages

  • Re: What did that thread indicate?
    ... >>> One cannot separate and fuse together at the same node. ... > single input stream. ... > must be a temporal correlation between two different signals in very ... was the pulse signal had some really nice properties. ...
    (comp.ai.philosophy)
  • Re: Simplest way to propagate a digital pulse?
    ... I want to apply a pulse to the first ... like to not have to drive a 25 foot clock line with a 100 device fan out. ... Of course, without a separate clock, I don't see how to accomplish ... On the falling edge of the input signal, ...
    (sci.electronics.design)
  • Re: Simplest way to propagate a digital pulse?
    ... pulse to the next module, etc., etc. ... each module's D input, and a separate, ... like to not have to drive a 25 foot clock line with a 100 device fan out. ... If a central controller turns the modules on, ...
    (sci.electronics.design)
  • Re: Simplest way to propagate a digital pulse?
    ... pulse to the next module, etc., etc. ... like to not have to drive a 25 foot clock line with a 100 device fan out. ... Of course, without a separate clock, I don't see how to accomplish ... On the falling edge of the input signal, ...
    (sci.electronics.design)
  • Re: how to build a clock with pulse for the hours!
    ... It's a novelty clock! ... order you've come to expect from a common watch. ... the desired pulse duration. ... Another possibility would be to use a tiny neodymium magnet on the tip ...
    (sci.electronics.basics)
Loading