MPC8315ECVRAGDA datasheet(62/112 Pages) FREESCALE

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MPC8315E PowerQUICC™ II Pro Processor Hardware Specifications, Rev. 0

Freescale Semiconductor

PCI Express

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:

•

Section 9.5.2, “AC Requirements for SGMII SD_REF_CLK and SD_REF_CLK”

•

Section 16.2, “AC Requirements for PCI Express SerDes Clocks”

15.2.4.1

Spread Spectrum Clock

SD_REF_CLK/SD_REF_CLK are not intended to be used with, and should not be clocked by, a spread

spectrum clock source.

15.3

SerDes Transmitter and Receiver Reference Circuits

Figure 49 shows the reference circuits for SerDes data lane’s transmitter and receiver.

Figure 49. SerDes Transmitter and Receiver Reference Circuits

The DC and AC specification of SerDes data lanes are defined in each interface protocol section below

(PCI Express or SGMII) in this document based on the application usage:

•

Section 9.5, “SGMII Interface Electrical Characteristics”

•

Section 16, “PCI Express”

Note that external AC Coupling capacitor is required for the above two serial transmission protocols with

the capacitor value defined in specification of each protocol section.

16 PCI Express

This section describes the DC and AC electrical specifications for the PCI Express bus of the MPC8315E.

16.1

DC Requirements for PCI Express SD_REF_CLK and

SD_REF_CLK

For more information, see Section 15.2, “SerDes Reference Clocks.”

Receiver

Transmitter

TXn

RXn

MPC8315ECVRAGDA Datasheet(PDF) 62 Page - Freescale Semiconductor, Inc