EP2AGX45DF29I5 Altera, EP2AGX45DF29I5 Datasheet - Page 265

• Manufacturer Part Number: EP2AGX45DF29I5
• Description: IC ARRIA II GX FPGA 45K 780FBGA
• Manufacturer: Altera
• Series: Arria II GXr

Specifications of EP2AGX45DF29I5

• Number Of Logic Elements/cells: 42959
• Number Of Labs/clbs: 1805
• Total Ram Bits: 3435
• Number Of I /o: 364
• Voltage - Supply: 0.87 V ~ 0.93 V
• Mounting Type: Surface Mount
• Operating Temperature: -40°C ~ 100°C
• Package / Case: 780-FBGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Number Of Gates: -

Chapter 8: High-Speed Differential I/O Interfaces and DPA in Arria II Devices
Source-Synchronous Timing Budget
December 2010 Altera Corporation
Transmitter Channel-to-Channel Skew
Receiver Skew Margin for Non-DPA Mode
f
Transmitter channel-to-channel skew (TCCS) is an important parameter based on the
Arria II transmitter in a source synchronous differential interface. This parameter is
used in receiver skew margin calculation.
TCCS is the difference between the fastest and slowest data output transitions,
including the TCO variation and clock skew. For LVDS transmitters, the TimeQuest
Timing Analyzer provides a TCCS report, which shows TCCS values for serial output
ports.
You can get the TCCS value from the TCCS report (report_TCCS) in the Quartus II
compilation report under the TimeQuest analyzer, or from the
Sheet
Changes in system environment, such as temperature, media (cable, connector, or
PCB), and loading, effect the receiver ’s setup and hold times; internal skew affects the
sampling ability of the receiver.
Different modes of LVDS receivers use different specifications, which can help in
deciding the ability to sample the received serial data correctly. In DPA mode, use
DPA jitter tolerance instead of receiver skew margin (RSKM).
In non-DPA mode, use RSKM, TCCS, and sampling window (SW) specifications for
high-speed source-synchronous differential signals in the receiver datapath. The
relationship between RSKM, TCCS, and SW is expressed by the RSKM equation
shown in
Equation 8–1.
Where:
■
■
■
■
You must calculate the RSKM value to decide whether or not the data can be sampled
properly by the LVDS receiver with the given data rate and device. A positive RSKM
value indicates the LVDS receiver can sample the data properly; a negative RSKM
indicates the receiver cannot sample the data properly.
TUI—the time period of the serial data.
RSKM—the timing margin between the receiver’s clock input and the data input
SW.
SW—the period of time that the input data must be stable to ensure that the data is
successfully sampled by the LVDS receiver. The sampling window is the device
property and varies with the device speed grade.
TCCS—the difference between the fastest and slowest data output transitions,
including the t
chapter.
Equation
CO
8–1:
variation and clock skew.
RSKM
Arria II Device Handbook Volume 1: Device Interfaces and Integration
=
TUI SW
--------------------------------------------- -
–
2
–
TCCS
Arria II Device Data
8–25