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2.3.3 PCI Express General Routing Guidelines
2.3.3.1 PCI Express Insertion Loss Budget with Slot Card
Figure 3
: PCI Express Insertion Loss Budget with Slot Card
The module transmit and receive insertion loss budgets are different due to the presence of the coupling
caps in the module transmit path. The module transmit path insertion loss budget shall be 4.65 dB (3.46
dB + 1.19 dB). The module receive path insertion loss budget shall be 3.46 dB. COM Express connector
loss is accounted for separately.
The Carrier Board transmit and receive insertion loss budgets are the same in this case. The Carrier
Board insertion loss budget shall be 4.40 dB. COM Express connector and slot card connector losses
are accounted for separately.
The slot card transmit and receive insertion loss budgets are different due to the presence of the
coupling caps in the slot card’s transmit path. The slot card’s transmit path insertion loss budget is 3.84
dB (2.65 dB + 1.19 dB) per the PCI Express Card Electromechanical Specification Revision 1.1. The slot
card’s receive path insertion loss budget is 2.65 dB per the same specification. Slot card connector loss
is accounted for separately.
