8T49N242_16 Datasheet, PDF (42/63 Pages) Integrated Device Technology – FemtoClock NG Universal Frequency Translator

8T49N242 Datasheet
Applications Information
Recommendations for Unused Input and Output
Pins
Inputs:
CLKx/nCLKx Input
For applications not requiring the use of one or more reference clock
inputs, both CLKx and nCLKx can be left floating. Though not
required, but for additional protection, a 1k resistor can be tied from
CLKx to ground. It is recommended that CLKx, nCLKx not be driven
with active signals when not selected.
LVCMOS Control Pins
All control pins have internal pullups or pulldowns; additional
resistance is not required but can be added for additional protection.
A 1k resistor can be used.
Outputs:
LVPECL Outputs
Any unused LVPECL output pair can be left floating. We recommend
that there is no trace attached. Both sides of the differential output
pair should either be left floating or terminated.
LVDS Outputs
Any unused LVDS output pair can be either left floating or terminated
with 100 across. If they are left floating there should be no trace
attached.
LVCMOS Outputs
Any LVCMOS output can be left floating if unused. There should be
no trace attached.
HCSL Outputs
All unused differential outputs can be left floating. We recommend
that there is no trace attached. Both sides of the differential output
pair should either be left floating or terminated.
©2016 Integrated Device Technology, Inc.
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Revision 6, November 1, 2016