MPC8533E_10 FREESCALE [Freescale Semiconductor, Inc], MPC8533E_10 Datasheet - Page 67

• Manufacturer Part Number: MPC8533E_10
• Description: Integrated Processor Hardware Specifications
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

The other detailed AC requirements of the SerDes reference clocks is defined by each interface protocol
based on application usage. Refer to the following sections for detailed information:
16.2.4.1
SD1_REF_CLK/SD1_REF_CLK were designed to work with a spread spectrum clock (+0 to –0.5%
spreading at 30–33 kHz rate is allowed), assuming both ends have same reference clock. For better results,
a source without significant unintended modulation should be used.
SD2_REF_CLK/SD2_REF_CLK are not intended to be used with, and should not be clocked by, a spread
spectrum clock source.
16.3
Figure 51
The DC and AC specification of SerDes data lanes are defined in the section below (PCI Express) in this
document based on the application usage:
Please note that external AC Coupling capacitor is required for the above serial transmission protocols
with the capacitor value defined in specification of each protocol section.
Freescale Semiconductor
•
•
SDn_REF_CLK
SDn_REF_CLK
SDn_REF_CLK
V
Section 17.2, “AC Requirements for PCI Express SerDes Clocks”
Section 17, “PCI Express”
CROSS MEDIAN
SerDes Transmitter and Receiver Reference Circuits
shows the reference circuits for SerDes data lane’s transmitter and receiver.
Spread Spectrum Clock
Figure 50. Single-Ended Measurement Points for Rise and Fall Time Matching
MPC8533E PowerQUICC III Integrated Processor Hardware Specifications, Rev. 4
Transmitter
Figure 51. SerDes Transmitter and Receiver Reference Circuits
50 Ω
50 Ω
SD1_TXn or
SD2_TXn
SD1_TXn or
SD2_TXn
V
V
CROSS MEDIAN
CROSS MEDIAN
SD1_RXn or
SD2_RXn
SD1_RXn or
SD2_RXn
SDn_REF_CLK
SDn_REF_CLK
V
CROSS MEDIAN
+ 100 mV
– 100 mV
50 Ω
50 Ω
Receiver
High-Speed Serial Interfaces (HSSI)
T
FALL
T
RISE
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