ICS85301
2:1
DIFFERENTIAL-TO-LVPECL MULTIPLEXER
Integrated
Circuit
Systems, Inc.
TERMINATION FOR 2.5V LVPECL OUTPUT
Figure 4A and Figure 4B show examples of termination for close to ground level. The R3 in Figure 4B can be eliminated
2.5V LVPECL driver.These terminations are equivalent to ter- and the termination is shown in Figure 4C.
minating 50Ω to VCC - 2V. For VCC = 2.5V, the VCC - 2V is very
2.5V
VCC=2.5V
2.5V
2.5V
VCC=2.5V
Zo = 50 Ohm
Zo = 50 Ohm
R1
250
R3
250
+
-
Zo = 50 Ohm
Zo = 50 Ohm
+
-
2,5V LVPECL
Driver
R1
50
R2
50
2,5V LVPECL
Driv er
R2
62.5
R4
62.5
R3
18
FIGURE 4A. 2.5V LVPECL DRIVERTERMINATION EXAMPLE
FIGURE 4B. 2.5V LVPECL DRIVERTERMINATION EXAMPLE
2.5V
VCC=2.5V
Zo = 50 Ohm
+
Zo = 50 Ohm
-
2,5V LVPECL
Driv er
R1
50
R2
50
FIGURE 4C. 2.5V LVPECLTERMINATION EXAMPLE
85301AK
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REV.A JANUARY 16, 2006
11
ICSI [ INTEGRATED CIRCUIT SOLUTION INC ]
