Nvidia Jetson TX2 Manual page 43

Parameter
Impedance
Trace Impedance
Reference Plane
Trace Length, Spacing & Skew
Trace loss characteristic @ 2.7GHz
Max PCB Via dist. from module conn. RBR/HBR
Max trace length from module to connector
RBR/HBR (Stripline / Microstrip)
HBR2 (Microstrip, 5x / 7x)
Trace spacing (Pair-Pair)
Microstrip (HBR/RBR)
Trace spacing
(Main Link to AUX)
Max Intra-pair (within pair) Skew
Max Inter-pair (pair-pair) Skew
Via
Max GND transition Via distance
Via Structure
Impedance dip
Recommende d via dimens ion
for impedance control
JETSON TX2/TX2i OEM PRODUCT | DESIGN GUIDE | 20180618
Requirement
Diff pair 100
90
85
GND
< 0.81
No requirement
HBR2 7.63 (0.3)
165 (1137.5)/(975)
HBR2 (Stripline) 101.6 (700)
89 (525) / 101.6 (600)
Stripline 3x
4x
Microstrip (HBR2) 5x to 7x
Stripline/Microstrip 3x / 5x
0.15 (1)
150
< 1x
≥97
≥92
Drill/Pad 200/400
Antipad >840
Via pitch ≥880
NVIDIA Jetson TX2/TX2i OEM Product Design Guide
Units Notes
Ω (±10%) 100Ω is the spec. target. 95/85Ω are
-
implementation options (Zdiff does not
account f or trace coupling)
95Ω should be used to support DP-HDMI co-
-
lay out as HDMI 2.0 requires 100Ω impedance
(see HDMI section for addition of series
resistor R
85Ω can be used if eDP/DP only & is
-
pref erable as it can provide better trace loss
characteristic performance. See Note 1.
dB/in The following max length is derived based on this
characteristic. See note 2.
mm (in)
175ps/inch assumption for Stripline, 150ps/inch
mm (ps) for Microstrip.
dielectric
dielectric
mm (ps)
- Do not perform length matching within
breakout region
- Do trace length matching before hitting
discontinuity (i.e. matching to <1ps
before the vias or any discontinuity to
minimize common mode conversion).
ps
diff pair pitch For signals switching reference layers, add
symmetrical GND stitching Via near signal Vias.
Ω @ 200ps
The via dimension must be required for the HDMI-
Ω @ 35ps
DP co-layout condition.
um
um
um
).
S
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