Re: [SI-LIST] : Cross-talk Concerns

Prasad Modali - Katmai Design (pmodali@pcocd2.intel.com)
Thu, 16 Jul 1998 17:16:22 -0700 (PDT)

Since you have a ground plane in between signals, there should
be minimum crosstalk between layer 1 and layer 3. Also, I don't
know if it's practical to change one of the ground plane to a
power plane. This will give you extra decoupling capacitance
if you're using same power supply for analog and digital.

my 2c.....prasad

Earlier, Alex Theodorou writes:
# I'm thinking about designing a 6 layer circuit board
# with the following stack-up:
#
# air
# ------layer 1: digital signal traces(50 ohm microstrip)/power
# distribution
# FR-4
# ------layer 2: digital ground plane
# FR-4
# ------layer 3: digital signal traces(50 ohm stripline)/power
# distribution
#
# FR-4
#
# ------layer 4: analog signal traces/power distribution
# FR-4
# ------layer 5: analog ground plane
# FR-4
# ------layer 6: analog signal traces/power distribution
# air
#
# If there is a trace on layer 1 which mirrors a trace
# on layer 3, do I need to be concerned with crosstalk induced
# by a signal on the layer 1 trace onto the layer 3 trace, even
# though there's a conducting plane (layer 2) between the two
# traces?
#
# Thanks in advance for any explanations.
#
# -Alex Theodorou
#

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Prasad Modali Phone: (916) 356-4438
MD6 Intel Corporation FM5-161 Fax: (916) 356-5719
Folsom California 95630 email: pmodali@pcocd2.intel.com
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