
ICS843002I-41
700MHZ, FEMTOCLOCK VCXO BASED SONET/SDH JITTER ATTENUATOR
IDT / ICS VCXO BASED SONET/SDH JITTER ATTENUATOR
15
ICS843002AKI-41 REV. B
APRIL 7, 2009
Termination for 2.5V LVPECL Outputs
Figure 6A and Figure 6B show examples of termination for 2.5V
LVPECL driver. These terminations are equivalent to terminating
50
Ω to V
CCO – 2V. For VCCO = 2.5V, the VCCO – 2V is very close to
ground level. The R3 in Figure 6B can be eliminated and the
termination is shown in Figure 6C.
Figure 6A. 2.5V LVPECL Driver Termination Example
Figure 6C. 2.5V LVPECL Driver Termination Example
Figure 6B. 2.5V LVPECL Driver Termination Example
2.5V LVPECL Driver
VCC = 2.5V
2.5V
50
Ω
50
Ω
R1
250
R3
250
R2
62.5
R4
62.5
+
–
2.5V LVPECL Driver
VCC = 2.5V
2.5V
50
Ω
50
Ω
R1
50
R2
50
+
–
2.5V LVPECL Driver
VCC = 2.5V
2.5V
50
Ω
50
Ω
R1
50
R2
50
R3
18
+
–