MPC8544VTALG datasheet(65/120 Pages) FREESCALE

65 / 120 page

MPC8544E PowerQUICC™ III Integrated Processor Hardware Specifications, Rev. 3

Freescale Semiconductor

High-Speed Serial Interfaces (HSSI)

Figure 43 shows the PCI output AC timing conditions.

Figure 43. PCI Output AC Timing Measurement Condition

16 High-Speed Serial Interfaces (HSSI)

The MPC8544E features two Serializer/Deserializer (SerDes) interfaces to be used for high-speed serial

interconnect applications.The SerDes1 dedicated for PCI Express data transfers. The SerDes2 can be used

for PCI Express and/or SGMII application. This section describes the common portion of SerDes DC

electrical specifications, which is the DC requirement for SerDes Reference Clocks. The SerDes data

lane’s transmitter and receiver reference circuits are also shown.

16.1

Signal Terms Definition

The SerDes utilizes differential signaling to transfer data across the serial link. This section defines terms

used in the description and specification of differential signals.

Figure 44 shows how the signals are defined. For illustration purpose, only one SerDes lane is used for

description. The figure shows waveform for either a transmitter output (SDn_TX and SDn_TX) or a

receiver input (SDn_RX and SDn_RX). Each signal swings between A Volts and B Volts where A > B.

Using this waveform, the definitions are as follows. To simplify illustration, the following definitions

assume that the SerDes transmitter and receiver operate in a fully symmetrical differential signaling

environment.

1. Single-Ended Swing

The transmitter output signals and the receiver input signals SDn_TX, SDn_TX, SDn_RX and

SDn_RX each have a peak-to-peak swing of A - B Volts. This is also referred as each signal wire’s

Single-Ended Swing.

2. Differential Output Voltage, VOD (or Differential Output Swing):

The Differential Output Voltage (or Swing) of the transmitter, VOD, is defined as the difference of

the two complimentary output voltages: VSDn_TX – VSDn_TX. The VOD value can be either positive

or negative.

CLK

Output Delay

tPCKHOV

High-Impedance

tPCKHOZ

Output

MPC8544VTALG Datasheet(PDF) 65 Page - Freescale Semiconductor, Inc