pi6c557-03 Pericom Semiconductor Corporation, pi6c557-03 Datasheet - Page 3

• Manufacturer Part Number: pi6c557-03
• Description: 100mhz, 125mhz Dual Pcie Clock Generator
• Manufacturer: Pericom Semiconductor Corporation

Application Information
Decoupling Capacitors
Decoupling capacitors of 0.01μF should be connected between
each VDD pin and the ground plane and placed as close to the
VDD pin as possible.
Crystal
Use a 25MHz fundamental mode parallel resonant crystal with
less than 300PPM of error across temperature.
Crystal Capacitors
C L = Crystals's load capacitance in pF
Crystal Capacitors (pF) = (C L - 8) *2
For example, for a crystal with 16pF load caps, the external ef-
fective crystal cap would be 16 pF. (16-8)*2=16.
Current Source (Iref) Reference Resistor - R R
If board target trace impedance is 50Ω,
then R R = 475Ω providing an IREF of 2.32 mA. The output
current (I OH ) is 6*IREF.
Output Termination
The PCI-Express differential clock outputs of the PI6C557-03
are open source drivers and require an external series resistor
and a resistor to ground. These resistor values and their allow-
able locations are shown in detail in the PCI-Express Layout
Guidelines section.
The PI6C557-03 can be confi gured for LVDS compatible
voltage levels. See the LVDS Compatible Layout Guidelines
section.
07-0274
3
Output Structures
R
R
IREF
=475
=2.3mA
Ω
See Output Termination
Sections
PCI Express Clock
6*IREF
PS8824C
PI6C557-03
12/14/07