ICS843001I-23 Datasheet, PDF (12/24 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL/LVCMOS FREQUENCY SYNTHESIZER

ICS843001I-23 Data Sheet
FEMTOCLOCK^® CRYSTAL/LVCMOS-TO-LVPECL/LVCMOS FREQUENCY SYNTHESIZER
Applications Information
Recommendations for Unused Input and Output Pins
Inputs:
Crystal Inputs
For applications not requiring the use of the crystal oscillator input,
both XTAL_IN and XTAL_OUT can be left floating. Though not
required, but for additional protection, a 1kΩ resistor can be tied from
XTAL_IN to ground.
CLK Input
For applications not requiring the use of the clock input, it can be left
floating. Though not required, but for additional protection, a 1kΩ
resistor can be tied from the CLK input to ground.
LVCMOS Control Pins
All control pins have internal pullups or pulldowns; additional
resistance is not required but can be added for additional protection.
A 1kΩ resistor can be used.
Outputs:
LVPECL Outputs
The 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.
LVCMOS Output
All unused LVCMOS output can be left floating. We recommend that
there is no trace attached.
ICS843001CGI-23 REVISION A OCTOBER 4, 2011
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©2011 Integrated Device Technology, Inc.