4–52
Altera Corporation
Stratix GX Device Handbook, Volume 3
February 2005
Transmission Lines
Figure 4–53. Simulation Results for a Grounded Differential Coplanar Wave Guide
Transmission Line Termination
High-speed signals require termination at the beginning, end, or both
sides of the transmission line to prevent the reflected signal from the ends
from corrupting the original signal. This section briefly describes several
termination techniques. For more details about each technique, refer to
AN315: Guidelines for Designing High-Speed FPGA PCBs.
Figure 4–54 shows the different termination techniques.
123
4
56
78
9
010
-70
-65
-60
-55
-50
-45
-75
-40
freq, GHz
Input Reflection Coefficient
12
345
6
78
9
010
-0.8
-0.7
-0.6
-0.5
-0.4
-0.3
-0.2
-0.1
-0.9
0.0
freq, GHz
Forward Transmission, dB
dB(S(1,1))
dB(S(2,1))