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ICS853052AG REV. B OCTOBER 24, 2007

ICS853052

DUAL LVCMOS/LVTTL-TO-DIFFERENTIAL 2.5V, 3.3V, 5V LVPECL MULTIPLEXER

PRELIMINARY

Figure 1A and Figure 1B show examples of termination for 2.5V

LVPECL driver. These terminations are equivalent to terminating

50

Ω to V

CC

- 2V. For V

CC

= 2.5V, the V

CC

- 2V is very close to ground

level. The R3 in Figure 1B can be eliminated and the termination

is shown in Figure 1C.

R2

62.5

Zo = 50 Ohm

R1

250

+

-

2.5V

2,5V LVPECL

Driv er

R4

62.5

R3

250

Zo = 50 Ohm

2.5V

VCC=2.5V

R1

50

R3

18

Zo = 50 Ohm

Zo = 50 Ohm

+

-

2,5V LVPECL

Driv er

VCC=2.5V

2.5V

R2

50

2,5V LVPECL

Driv er

VCC=2.5V

R1

50

R2

50

2.5V

Zo = 50 Ohm

Zo = 50 Ohm

+

-

For applications not requiring the use of a clock input, it can

be left floating. Though not required, but for additional

protection, a 1k

Ω resistor can be tied from the Dx input to

ground.