Re: [SI-LIST] : Precision Clocking

D. C. Sessions (dc.sessions@tempe.vlsi.com)
Mon, 06 Apr 1998 14:29:02 -0700

GEisler wrote:
>
> To designers interested in precision clocks:
>
> What level of precision is desirable/useful in clock distribution nets for
> boards and systems?
>
> Our current "clock spreader" chip provides 18 outputs, all within a 25
> picosecond band with very low jitter. This is the state of the art in the
> semiconductor tester world. Are there requirements for this level of timing
> precision in applications outside of ATE? We would very much like to hear
> thoughts and opinions on this subject.

You didn't say, but I trust that they're differential signals?
Otherwise the 25ps is irrelevant since SSO crosstalk will dwarf
it and threshold shift accounts for at least an order of magnitude
more.

-- 
D. C. Sessions
dc.sessions@tempe.vlsi.com