Table of Contents
Advertisement
2.5.4.1 10GB LAN KR Guidelines
Table 16 : 10GB LAN KR Trace Length Guidelines
Parameter
Signal Group
Differential Impedance Target
Single End
Isolation to equivalent pairs
Isolation to other signal groups
Tx/Rx Spacing
LA + LB
Lc
Max length of LA+LB+LC
Length matching
Reference Plane
Carrier Board Via Usage
AC coupling
Notes:
1.H is height above reference plane.
2.Equivalent pairs are TX to TX or RX to RX(Noninterleaved)
3.AC caps are recommended to be placed close to KR device side (avoid placing AC cpas on mid-bus).
Main Route Guidelines
10GB LAN KR
100Ω±10
50Ω±10%
12H (MS) and 5H(DS)
15H (MS) and 7H (DS)
15H(MS) and 7H (DS)
SOM-5992 Layout Checklist
Carrier Board Length
Slot Card:
28"
Device Down:
28"
Differential pairs (intra-pair): Max.
GND referencing preferred
Min 40-mil trace edge-to-major plane edge spacing
GND stitching vias required next to signal vias if
transitioning layers between GND layers
Power referencing acceptable if stitching caps are
used
Max. 2 vias per TX trace, Max. 3 vias per RX trace
The AC coupling capacitors for the TX lines are
incorporated on the COM Express Module. The AC
coupling capacitors for RX signal lines have to be
implemented on the customer COM Express Carrier
Board. Capacitor type: X7R, 100nF ±10%, 16V, shape
0402.
５９
±5mls
Notes
1,2
1
1
3
Advertisement
Table of Contents
