mpc8378e Freescale Semiconductor, Inc, mpc8378e Datasheet - Page 85

• Manufacturer Part Number: mpc8378e
• Description: Powerquicc Ii Pro Processor Hardware Specifications
• Manufacturer: Freescale Semiconductor, Inc

20.2.3
The following list provides information about interfacing with other differential signaling levels.
Freescale Semiconductor
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With on-chip termination to SGND_SRDSn (xcorevss), 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 mV 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.
Interfacing With Other Differential Signaling Levels
Figure 59
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 the 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 device SerDes reference clock receiver requirement
provided in this document.
MPC8378E PowerQUICC II Pro Processor Hardware Specifications, Rev. 3
to
Figure 62
below are for conceptual reference only. Due to the
NOTE
High-Speed Serial Interfaces (HSSI)
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