PLX Technology PEX 8311RDK, Hardware Reference Manual

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PEX 8311RDK Hardware Reference Manual, Version 0.90
18 © 2005 PLX Technology, Inc. All rights reserved.
Figure 4-2. PEX 8311RDK Decoupling Capacitor Footprints
4.2.3 PCB Stackup
The PEX 8311RDK is an 8-layer, 60-mil thick PCB. The target signal impedance for all routing layers is
55 Ohms ±10% single-ended impedance and 100 Ohms ±5% differential. Figure 4-3 details the layers
used in the PCB manufactuer. The thickness of the various layers is detailed in Table 4-2. Layer
thickness.
SOLDERMASK
PREPEG
LAMINATE
PREPEG
LAMINATE
PREPEG
LAMINATE
PREPEG
SOLDERMASK
L8, SIGNAL 4
L1, SIGNAL 1
L2, GROUND
L3, SIGNAL 2
L4, POWER
L5, POWER
L6, SIGNAL 3
L7, GROUND
Controlled Impedance
Controlled Impedance
Controlled Impedance
Controlled Impedance
Figure 4-3. PEX 8311RDK Stackup