NVIDIA Jetson TX2/TX2i OEM Product Design Guide
JETSON TX2/TX2i OEM PRODUCT | DESIGN GUIDE | 20180618
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Parameter
Requirement
Units
Notes
Impedance
Trace Impedance
Diff pair
100
90
85
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
S
).
-
85Ω can be used if eDP/DP only & is
pref erable as it can provide better trace loss
characteristic performance. See Note 1.
Reference Plane
GND
Trace Length, Spacing & Skew
Trace loss characteristic @ 2.7GHz
< 0.81
dB/in
The following max length is derived based on this
characteristic. See note 2.
Max PCB Via dist. from module conn.
RBR/HBR
HBR2
No requirement
7.63 (0.3)
mm (in)
Max trace length from module to connector
RBR/HBR
(Stripline / Microstrip)
HBR2
(Stripline)
HBR2
(Microstrip, 5x / 7x)
165 (1137.5)/(975)
101.6 (700)
89 (525) / 101.6 (600)
mm (ps)
175ps/inch assumption for Stripline, 150ps/inch
for Microstrip.
Trace spacing (Pair-Pair)
Stripline
Microstrip (
HBR/RBR
)
Microstrip (
HBR2
)
3x
4x
5x to 7x
dielectric
Trace spacing
Stripline/Microstrip
(Main Link to AUX)
3x / 5x
dielectric
Max Intra-pair (within pair) Skew
0.15 (1)
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).
Max Inter-pair (pair-pair) Skew
150
ps
Via
Max
GND
transition Via distance
< 1x
diff pair pitch
For signals switching reference layers, add
symmetrical
GND
stitching Via near signal Vias.
Via Structure
Impedance dip
Recommende d via dimens ion
Drill/Pad
for impedance control
Antipad
Via pitch
≥
97
≥
92
200/400
>840
≥880
Ω
@ 200ps
Ω
@ 35ps
um
um
um
The via dimension must be required for the HDMI-
DP co-layout condition.
