EP2AGX95EF29C6N Datasheet, PDF (279/380 Pages) Altera Corporation – Device Interfaces and Integration

Chapter 8: High-Speed Differential I/O Interfaces and DPA in Arria II Devices
Differential Pin Placement Guidelines
8–33
Guidelines for DPA-Disabled Differential Channels
When you use DPA-disabled channels, you must adhere to the guidelines in the
following sections.
DPA-Disabled Channel Driving Distance
Each PLL can drive all the DPA-disabled channels in the entire bank.
Using Corner and Center PLLs in Arria II GX Devices
You can use a corner PLL to drive all transmitter channels and you can use a center
PLL to drive all DPA-disabled receiver channels in the same I/O bank. In other
words, you can drive a transmitter channel and a receiver channel in the same LAB
row by two different PLLs, as shown in Figure 8–27.
Figure 8–27. Corner and Center PLLs Driving DPA-Disabled Differential I/Os in the Same Bank
Corner
PLL
Corner
PLL
Reference
CLK
Diff RX Diff TX
Diff RX
Diff RX
Diff RX
Diff RX
Diff RX
Diff RX
Diff RX
Diff RX
Diff TX
Diff TX
Diff TX
Diff TX
Diff TX
Diff TX
Diff TX
Diff TX
Reference
CLK
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
DPA-disabled
Diff I/O
Channels
driven by
Corner
PLL
No
separation
buffer
needed
Channels
driven by
Center
PLL
Diff RX Diff TX
Reference
CLK
DPA -disabled
Diff I /O
Reference
CLK
Center
PLL
Center
PLL
July 2012 Altera Corporation
Arria II Device Handbook Volume 1: Device Interfaces and Integration