EP2AGX95EF29C6N Datasheet, PDF (194/380 Pages) Altera Corporation – Device Interfaces and Integration

6–30
Chapter 6: I/O Features in Arria II Devices
Termination Schemes for I/O Standards
Differential I/O Standards Termination
Arria II devices support differential SSTL-2 and SSTL-18, differential HSTL-18,
HSTL-15, HSTL-12, LVDS, LVPECL, RSDS, and mini-LVDS. Figure 6–13 through
Figure 6–14 show the details of various differential I/O terminations on Arria II
devices.
1 Differential HSTL and SSTL outputs are not true differential outputs. They use two
single-ended outputs with the second output programmed as inverted.
Figure 6–13 shows the details of differential SSTL I/O standard termination on
Arria II devices.
Figure 6–13. Differential SSTL I/O Standard Termination for Arria II Devices
Termination
Differential SSTL Class I
External
On-Board
Termination
Transmitter
VTT VTT
25 Ω
50 Ω
50 Ω
25 Ω
50 Ω
50 Ω
Receiver
Differential SSTL Class II
Transmitter
VTT VTT
VTT VTT
50 Ω
25 Ω
50 Ω 50 Ω
50 Ω
50 Ω
25 Ω
50 Ω
Receiver
R _S OCT for
Arria II GX
Devices
Differential SSTL Class I
Series OCT 50 Ω
Transmitter
VTT
50 Ω
Z0= 50 Ω
VTT
Z0= 50 Ω
50 Ω
Receiver
Differential SSTL Class II
Series OCT 25 Ω
VTT
VTT
50 Ω
50 Ω
Z0= 50 Ω
VTT
VTT
50 Ω
50 Ω
Z0= 50 Ω
Transmitter
Receiver
Differential SSTL Class I
Series OCT 50 Ω
R _S OCT and
R _T OCT for
Arria II GZ
Devices
Transmitter
Z0= 50 
Z0= 50 
VCCIO
100 
Parallel OCT
100 
100  _VCCIO
GND
100 
100 
GND
Receiver
Differential SSTL Class II
Series OCT 25 Ω
Transmitter
VTT
50 
Z0= 50 
VTT
50 
Z0= 50 
VCCIO
100 
Parallel OCT
100 
100  _VCCIO
GND
100 
100 
GND
Receiver
Arria II Device Handbook Volume 1: Device Interfaces and Integration
December 2011 Altera Corporation