mpc8568e Freescale Semiconductor, Inc, mpc8568e Datasheet - Page 66

• Manufacturer Part Number: mpc8568e
• Description: Mpc8568e Powerquicc Iii Processor
• Manufacturer: Freescale Semiconductor, Inc

High-Speed Serial Interfaces (HSSI)
13.2.3
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With on-chip termination to SCOREGND, the differential reference clocks inputs are HCSL
(High-Speed Current Steering Logic) compatible DC-coupled.
Many other low voltage differential type outputs like LVDS (Low Voltage Differential Signaling)
can be used but may need to be AC-coupled due to the limited common mode input range allowed
(100 to 400 mV) for DC-coupled connection.
LVPECL outputs can produce signal with too large amplitude and may need to be DC-biased at
clock driver output first, then followed with series attenuation resistor to reduce the amplitude, in
addition to AC-coupling.
MPC8568E/MPC8567E PowerQUICC III™ Integrated Processor Hardware Specifications, Rev. 0
Interfacing With Other Differential Signaling Levels
Figure 44
fact that clock driver chip's internal structure, output impedance and
termination requirements are different between various clock driver chip
manufacturers, it is very possible that the clock circuit reference designs
provided by clock driver chip vendor are different from what is shown
below. They might also vary from one vendor to the other. Therefore,
Freescale Semiconductor can neither provide the optimal clock driver
reference circuits, nor guarantee the correctness of the following clock
driver connection reference circuits. The system designer is recommended
to contact the selected clock driver chip vendor for the optimal reference
circuits with the MPC8568 SerDes reference clock receiver requirement
provided in this document.
to
Figure 47
below are for conceptual reference only. Due to the
NOTE
Freescale Semiconductor