mpc8568e Freescale Semiconductor, Inc, mpc8568e Datasheet - Page 67

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

Figure 44
assumes that the DC levels of the clock driver chip is compatible with MPC8568 SerDes reference clock
input’s DC requirement.
Figure 45
Since LVDS clock driver’s common mode voltage is higher than the MPC8568 SerDes reference clock
input’s allowed range (100 to 400mV), AC-coupled connection scheme must be used. It assumes the
LVDS output driver features 50-Ω termination resistor. It also assumes that the LVDS transmitter
establishes its own common mode level without relying on the receiver or other external component.
Freescale Semiconductor
HCSL CLK Driver Chip
LVDS CLK Driver Chip
Total 50 Ω. Assume clock driver’s
output impedance is about 16 Ω.
Clock Driver
Clock Driver
Clock Driver
Clock Driver
Figure 44. DC-Coupled Differential Connection with HCSL Clock Driver (Reference Only)
Figure 45. AC-Coupled Differential Connection with LVDS Clock Driver (Reference Only)
shows the SerDes reference clock connection reference circuits for HCSL type clock driver. It
shows the SerDes reference clock connection reference circuits for LVDS type clock driver.
MPC8568E/MPC8567E PowerQUICC III™ Integrated Processor Hardware Specifications, Rev. 0
CLK_Out
CLK_Out
CLK_Out
CLK_Out
CLK_Out
33 Ω
10 nF
10 nF
33 Ω
Clock driver vendor dependent
source termination resistor
100 Ω differential PWB trace
100 Ω differential PWB trace
SD_REF_CLK
SD_REF_CLK
SD_REF_CLK
SD_REF_CLK
50 Ω
50 Ω
High-Speed Serial Interfaces (HSSI)
50 Ω
50 Ω
MPC8568E
MPC8568E
SerDes Refer.
CLK Receiver
SerDes Refer.
CLK Receiver
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