NVIDIA Jetson TX2/TX2i OEM Product Design Guide
JETSON TX2/TX2i OEM PRODUCT | DESIGN GUIDE | 20180618
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Inter-pair
spacing
-
Stripline structure in a GSSG structure is assumed; it
holds in broadside-coupled stripline structure
-
All v alues are in terms of minimum dielectric height
Max length
Breakout
Main-route
11
Max trace
length - LBRK
mm
Trace Spacing
–
for TX/RX interleaving
Trace Spacing
Pair-Pair (inter-pair)
Microstrip / Stripline
To plane & capacitor pad
Microstrip / Stripline
To unre lated high-speed signals
Microstrip / Stripline
4x / 3x
4x / 3x
4x / 3x
dielectric
Via
Topology
-
Y -pattern is
recommended
-
Keep sy mmetry
Y-pattern helps with
Xtalk suppression. It
can also reduce the
limit of pair-pair
distance. Need review
(NEXT/FEXT check) if
via placement is not Y-
pattern.
GND
via
-
Place ground v ias as
sy mmetrically as
possible to data pair
v ias
-
up to 4 signal v ias (2
dif f pairs) can share a
single GND return v ia
GND
via is used to maintain return path, while its Xtalk
suppression is limited
Max # of Vias
PTH vias
Micro Vias
4
Not limited as long as total channel loss meets IL spec
Max Via Stub Length
0.4
mm
long via stub requires review (IL & resonance dip check)
Serpentine
Min bend angle
135
deg (
α
)
S1 must be taken care in order
to consider Xtalk to adjacent
pair
Dimension
Min A Spacing
Min B, C Length
Min Jog Width
4x
1.5x
3x
Trace
width
Added-on Components
Placement Order
Chip
̶
AC capacitor (TX only)
̶
common mode choke
̶
ESD
̶
Connector
AC Cap
Value
Min/Max
0.075 / 0.2
uF
Only required for TX pair when routed to connector
Location (max length to adjacent discontinuity)
8
mm
Discontinuity is connector, via, or component pad
Voiding
GND
/
PWR
void under/above
cap is preferred
Voiding is required if AC cap size is 0603 or larger
ESD
(the usage of ESD is optional. A design should include the footprint for ESD as a stuffing option)
Preferred device
e.g. SEMTECH RClamp0524p
Max Junction capacitance (IO to GND)
0.8
pF
Footprint
Pad should be on the net
–
not trace stub
Location (max length to adjacent discontinuity)
8 (53)
mm (ps)
Discontinuity is connector, via, or component pad
