mpc8641 Freescale Semiconductor, Inc, mpc8641 Datasheet - Page 77

• Manufacturer Part Number: mpc8641
• Description: Integrated Host Processor Hardware Specifications
• Manufacturer: Freescale Semiconductor, Inc

Serial RapidIO
Figure 52. Compliance Test/Measurement Load
15 Serial RapidIO
This section describes the DC and AC electrical specifications for the RapidIO interface of the MPC8641,
for the LP-Serial physical layer. The electrical specifications cover both single and multiple-lane links.
Two transmitter types (short run and long run) on a single receiver are specified for each of three baud
rates, 1.25, 2.50, and 3.125 GBaud.
Two transmitter specifications allow for solutions ranging from simple board-to-board interconnect to
driving two connectors across a backplane. A single receiver specification is given that will accept signals
from both the short run and long run transmitter specifications.
The short run transmitter specifications should be used mainly for chip-to-chip connections on either the
same printed circuit board or across a single connector. This covers the case where connections are made
to a mezzanine (daughter) card. The minimum swings of the short run specification reduce the overall
power used by the transceivers.
The long run transmitter specifications use larger voltage swings that are capable of driving signals across
backplanes. This allows a user to drive signals across two connectors and a backplane. The specifications
allow a distance of at least 50 cm at all baud rates.
All unit intervals are specified with a tolerance of +/– 100 ppm. The worst case frequency difference
between any transmit and receive clock will be 200 ppm.
To ensure interoperability between drivers and receivers of different vendors and technologies, AC
coupling at the receiver input must be used.
15.1
DC Requirements for Serial RapidIO SD n _REF_CLK and
SD n _REF_CLK
For more information, see
Section 13.2, “SerDes Reference Clocks.”
MPC8641 and MPC8641D Integrated Host Processor Hardware Specifications, Rev. 2
Freescale Semiconductor
77