Nvidia Jetson TX2 Manual page 44

Parameter
Topology
GND via
Max # of Vias
Max Via Stub Length
Serpentine
Min bend angle
Dimension
AC Cap
Value
Max Dist. from A C cap
to connector
Voiding
Connector
Voiding
Keep critical eDP related traces including differential clock/data traces & RSET trace away from other signal traces or unrelated power traces/areas or
power supply components
Notes: For eDP/DP, the spec puts a higher priority on the trace loss characteristic than on the impedance. However, b efore
1.
selecting 85Ω for impedance, it is important to make sure the selected stack-up, material & trace dimension can achieve
the needed low loss characteristic.
Longer trace lengths may be possible if the total trace loss is equal to or better than the target. If the loss is greater, the
2.
max trace lengths will need to be reduced.
The average of the differential signals is used for length matching.
3.
Do not perform length matching within breakout region. Recommend doing trace length matching to <1ps before Vias
4.
or any discontinuity to minimize common mode conversion
JETSON TX2/TX2i OEM PRODUCT | DESIGN GUIDE | 20180618
Requirement
-
Y -pattern is recommended
-
keep sy mmetry
Xtalk suppression is best using the Y-pattern.
It can also reduce the limit of pair-pair
distance.
For in-line via, the distance from a via of one
lane to the adjacent via from other lane >=
1.2mm center-center.
Place GND via as symmetrically as possible to
data pair vias. Up to 4 signal vias (2 diff
pairs) can share a single GND return via
PTH vias 4 if all vias are PTH via
Micro Vias Not limited as long as total channel loss
meets IL spec
0.4
135
Min A Spacing 4x
Min B, C Length 1.5x
Min Jog Width 3x
0.1
RBR/HBR No requirement
HBR2 0.5
RBR/HBR No requirement
HBR2 Voiding required
RBR/HBR No requirement
HBR2 Voiding required
NVIDIA Jetson TX2/TX2i OEM Product Design Guide
Units Notes
GND via is used to maintain return path, while its
Xtalk suppression is limited
mm
deg (a) S1 must be taken care in
Trace width order to consider Xtalk to
adjacent pair
uF Discrete 0402
in
HBR2: Voiding the plane directly under the pad 3-
4 mils larger than the pad size is recommended.
HBR2: Standard DP Connector: Voiding
requirement is stack-up dependent. For typical
stack-ups, voiding on the layer under the
connector pad is required to be 5.7mil larger than
the connector pad.
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