G
Guy Macon
- Jan 1, 1970
- 0
I recently got into a conversation in comp.arch concerning
how fast signals propagate and how far they can travel in
microprocessor wiring.
Some of the posters seem to think that wafer-scale traces/wires
are a lot slower than PWB-scale and system-scale traces/wires
because they are RC transmission lines, not LC.
I did a few crude simulations and it seems to me that the
RC slows down the risetime on single edges and cuts the
amplitude way down on high frequency clock signals, but
I can't see any reason to think that the propagation would
be a lot slower than the usual 60%-80% of C rule of thumb.
I am familiar with normal board and system level transmission
lines such as ECL, stripline, coax, etc., but have never done
any work with chip-scale electronics. Does anyone here know
how fast and how far one can move a signal across a die? Thanks!
how fast signals propagate and how far they can travel in
microprocessor wiring.
Some of the posters seem to think that wafer-scale traces/wires
are a lot slower than PWB-scale and system-scale traces/wires
because they are RC transmission lines, not LC.
I did a few crude simulations and it seems to me that the
RC slows down the risetime on single edges and cuts the
amplitude way down on high frequency clock signals, but
I can't see any reason to think that the propagation would
be a lot slower than the usual 60%-80% of C rule of thumb.
I am familiar with normal board and system level transmission
lines such as ECL, stripline, coax, etc., but have never done
any work with chip-scale electronics. Does anyone here know
how fast and how far one can move a signal across a die? Thanks!