Gerhard Fiedler wrote:
>
> At 15:30 03/08/99 -0500, Wagner Lipnharski wrote:
> >just updating information:
> >In the Texas CD74HCT597 data sheet, what avoids Q+1=Q-1
> >in the same cycle, is the timing tPLH (60ns).
> >Take a look at (page 8):
> >http://www-s.ti.com/sc/psheets/schs191/schs191.pdf
>
> yes, that's why i think it =usually= might work. but in the same place
> there is a Th(h), the minimum data hold time. i didn't find a spec on that
> in this texas sheet, but in the motorola data sheet
> http://www.mot-sps.com/books/dl129/pdf/mc74hc597rev6.pdf it is spec'd with
> min 5ns. this means it works as long as the propagation delay is not
> shorter than 5ns, which seems not to be specified.
>
> i seem to recall some discussion on this here; does anybody have
> experiences with a problem with chaining shift registers?
>
> ge

Well, yes, they don't specify even the minimum propagation time,
so supposing that in China there are always more butterflies
flying than resting, it will works (if not otherwise observed).
I already did some cascades and never got a problem, well not
with the 597, but other works fine.
wagner.