78P2351R

Serial 155M

NRZ to CMI Converter

Page: 21 of 31

Rev. 2.1

TRANSMITTER SPECIFICATIONS FOR CMI INTERFACE

Bit Rate: 155.52Mbits/s

± 20ppm

Code: Coded Mark Inversion (CMI)

Relevant Specification: ITU-T G.703, Telcordia GR-253, ANSI T1.102

With the coaxial output port driving a 75

Ω load, the output pulses conform to the templates in Figures 8 and 9.

These specifications are tested during production test. Consult application note for reference schematic, layout

guidelines, and recommended transformers.

PARAMETER

CONDITION

MIN

NOM

MAX

UNIT

Peak-to-peak Output Voltage

(Fuse-trimmed to nominal target at

final test)

Template, steady state

0.9

1.04

1.1

V

Rise/ Fall Time

10-90%

2

ns

Negative Transitions

-0.1

0.1

Positive Transitions at Interval

Boundaries

-0.5

0.5

Transition Timing Tolerance

Positive Transitions at mid-

interval

-0.35

0.35

ns

The following specifications are not tested during production test. They are included for information only.

Note that the return loss depends on the board layout and the particular transformer used.

PARAMETER

CONDITION

MIN

NOM

MAX

UNIT

Output Impedance

Driver is open drain

1

8

M

Ω

pF

Return Loss

7MHz to 240MHz

15

dB