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March 31, 2008

IDT80KSW0004

Datasheet

The differential return loss, S11, of the transmitter in each case shall be better than

-10 dB for (Baud Frequency)/10 < Freq(f) < 625 MHz, and

-10 dB + 10log(f/625 MHz) dB for 625 MHz <= Freq(f) <= Baud Frequency

The reference impedance for the differential return loss measurements is 100 Ohm resistive. Differential return loss includes contributions from on-

chip circuitry, chip packaging and any off-chip components related to the driver. The output impedance requirement applies to all valid output levels.

The CPS-12 satisfies the specification requirement that the 20%-80% rise/fall time of the transmitter, as measured at the transmitter output, in each

case has a minimum value 60 ps.

Similarly the timing skew at the output of an LP-Serial transmitter between the two signals that comprise a differential pair does not exceed 25 ps at

1.25 GB, 20 ps at 2.50GB and 15 ps at 3.125 GB.

Table 14 Short Run Transmitter AC Timing Specifications - 1.25 GBaud

Table 15 Short Run Transmitter AC Timing Specifications - 2.5 GBaud

Symbol

Parameter

Range

Unit

Notes

Min

Max

VO

Output Voltage

-0.40

2.30

Volts

Voltage relative to COM-

MON of either signal com-

prising a differential pair.

VDIFF PP

Differential Output Voltage

500

1000

mV p-p

JD

Deterministic Jitter

-

0.17

UI p-p

JT

Total Jitter

-

0.35

UI p-p

SMO

Multiple Output Skew

-

1000

ps

Skew at the transmitter

output between lanes of a

multilane link

UI

Unit Interval

800

800

ps

+/- 100 ppm

Symbol

Parameter

Range

Unit

Notes

Min

Max

VO

Output Voltage

-0.40

2.30

Volts

Voltage relative to COM-

MON of either signal com-

prising a differential pair.

VDIFF PP

Differential Output Voltage

500

1000

mV p-p

JD

Deterministic Jitter

-

0.17

UI p-p

JT

Total Jitter

-

0.35

UI p-p

SMO

Multiple Output Skew

-

1000

ps

Skew at the transmitter

output between lanes of a

multilane link

UI

Unit Interval

400

400

ps

+/- 100 ppm