Termination for 2.5 V LVPECL Outputs
Figure 3.9 2.5 V LVPECL Termination Example, Option 1 on page 14
and
Figure 3.10 2.5 V LVPECL Termination Example, Option 2
show examples of termination for the 2.5 V LVPECL driver option. These terminations are equivalent to terminating 50 Ω
to VDDO – 2 V. For VDDO = 2.5 V, the VDDO – 2 V is very close to ground level. The R3 in
Figure 3.10 2.5 V LVPECL Termination
can be optionally eliminated using the termination shown in
Figure 3.9 2.5 V LVPECL Termination
.
2.5V
2.5V
2.5V LVPECL
Driver
Zo=50 Ω
Zo=50 Ω
R1
62.5 Ω
R2
62.5 Ω
+
-
Input
R4
250 Ω
R3
250 Ω
2.5V
RTT = 29.5 Ω
Si5332
LVPECL Output
Driver
Figure 3.9. 2.5 V LVPECL Termination Example, Option 1
2.5V
2.5V
2.5V LVPECL
Driver
Zo=50 Ω
Zo=50 Ω
R1
50Ω
R2
50Ω
+
-
Input
R3
18Ω
Si5332
LVPECL Output
Driver
Figure 3.10. 2.5 V LVPECL Termination Example, Option 2
Si5332 Data Sheet • Functional Description
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
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Rev. 1.3 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • November 16, 2021
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