ICS853S031I Data Sheet

LOW SKEW, 1-TO-9, DIFFERENTIAL-TO-2.5V, 3.3V LVPECL/ECL FANOUT BUFFER

ICS853S031BYI REVISION A AUGUST 17, 2011

13

©2011 Integrated Device Technology, Inc.

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 VCCO – 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

VCCO = 2.5V

2.5V

2.5V

50

Ω

50

Ω

R1

250

R3

250

R2

62.5

R4

62.5

+

–

2.5V LVPECL Driver

VCCO = 2.5V

2.5V

50

Ω

50

Ω

R1

50

R2

50

+

–

2.5V LVPECL Driver

VCCO = 2.5V

2.5V

50

Ω

50

Ω

R1

50

R2

50

R3

18

+

–