5V41235
2 OUTPUT PCIE GEN1/2/3 SYNTHESIZER
Layout Guidelines
SRC Reference Clock
Common Recommendations for Differential Routing
L1 length, route as non-coupled 50ohm trace
L2 length, route as non-coupled 50ohm trace
L3 length, route as non-coupled 50ohm trace
Dimension or Value
0.5 max
0.2 max
0.2 max
33
Unit Figure
inch
inch
inch
ohm
ohm
1
1
1
1
1
Rs
Rt
49.9
Down Device Differential Routing
L4 length, route as coupled microstrip 100ohm differential trace
L4 length, route as coupled stripline 100ohm differential trace
2 min to 16 max
1.8 min to 14.4 max
inch
inch
1
1
Differential Routing to PCI Express Connector
L4 length, route as coupled microstrip 100ohm differential trace
L4 length, route as coupled stripline 100ohm differential trace
0.25 to 14 max
0.225 min to 12.6 max
inch
inch
2
2
Figure 1: Down Device Routing
L2
L1
Rs
Rs
L4
L4'
L2'
L1'
Rt
Rt
HCSL Output Buffer
PCI Express
Down Device
REF_CLK Input
L3' L3
Figure 2: PCI Express Connector Routing
L2
L1
Rs
L4
L4'
L2'
L1'
Rs
Rt
Rt
HCSL Output Buffer
PCI Express
Add-in Board
REF_CLK Input
L3' L3
IDT® 2 OUTPUT PCIE GEN1/2/3 SYNTHESIZER
5
5V41235
MAY 5, 2017