Is it a problem when I keep different LVDS traces really close to each other
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\$\begingroup\$ What does close mean to you? More than five times the thickness of the prepreg? No problem then. \$\endgroup\$– JankaCommented Nov 8, 2020 at 17:04
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According to a TI app note:
The distance between two adjacent LVDS pairs should be greater than or equal to twice the distance between the two individual conductors of a single LVDS pair.
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\$\begingroup\$ Some people could be tempted to move the conductors of a pair closer to each other. \$\endgroup\$– JankaCommented Nov 8, 2020 at 17:07
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\$\begingroup\$ Our default routing guidelines are 25 mil separation between differential pairs, and 15 mil separation between conductors of a diff pair. So not quite the 2X of the TI recommendation. \$\endgroup\$– SteveShCommented Nov 8, 2020 at 18:03
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\$\begingroup\$ @SteveSh - if you want to ensure that the characteristic impedance of the differential pair matches the termination then the spacing will depend upon trace width and proximity of ground plane (prepress thickness if there is a ground plane on the adjacent layer). I normally use 3x clearance. \$\endgroup\$ Commented Nov 8, 2020 at 18:13
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\$\begingroup\$ @Kevin White - Agreed, But the question was about closeness of LVDS diif pairs to one another. \$\endgroup\$– SteveShCommented Nov 8, 2020 at 21:45