ICS854S204I Datasheet, PDF (13/19 Pages) Integrated Device Technology – LOW SKEW, DUAL, PROGRAMMABLE 1-TO-2 DIFFERENTIALTO-LVDS, LVPECL FANOUT BUFFER

ICS854S204I
LOW SKEW, DUAL, 1-TO-2 DIFFERENTIAL-TO-LVDS, LVPECL FANOUT BUFFER
TERMINATION FOR 2.5V LVPECL OUTPUTS
Figure 5A and Figure 5B show examples of termination for 2.5V
LVPECL driver. These terminations are equivalent to terminating
50Ω to V – 2V. For V = 2.5V, the V – 2V is very close to ground
DD
DD
DD
level. The R3 in Figure 5B can be eliminated and the termination
is shown in Figure 5C.
VC CO=2. 5V
Zo = 50 Ohm
Zo = 50 Ohm
2,5V LVPECL
Driv er
2. 5V
R1
R3
250
250
2.5V
+
-
R2
62. 5
R4
62. 5
VCCO=2.5V
Zo = 50 Ohm
Zo = 50 Ohm
2,5V LVPECL
Driv er
2. 5V
+
-
R1
R2
50
50
R3
18
FIGURE 5A. 2.5V LVPECL DRIVER TERMINATION EXAMPLE
FIGURE 5B. 2.5V LVPECL DRIVER TERMINATION EXAMPLE
VCCO=2.5V
Zo = 50 Ohm
Zo = 50 Ohm
2,5V LVPECL
Driv er
2. 5V
+
-
R1
R2
50
50
FIGURE 5C. 2.5V LVPECL TERMINATION EXAMPLE
IDT^™ / ICS^™ LVDS, LVPECL FANOUT BUFFER
13
ICS854S204BGI REV. A JUNE 4, 2008