AND8090 Datasheet, PDF (17/20 Pages) ON Semiconductor – AC Characteristics of ECL Devices

AND8090/D
Deterministic Jitter
Deterministic jitter (DJ, also referred to as “data” or
“systematic” jitter) is characterized by bounded
non–Gaussian probability density functions. Deterministic
jitter includes Duty Cycle Distortion (DCD) which is
specified as Duty Cycle Skew or Pulse Skew on data sheets
(refer to the “Duty Cycle Skew” section). Determistic jitter
is defined for a specific test pattern, and is specified as a
peak−to−peak value.
Total DJ Test Setup
The total DJ test setup shown in Figure 40 is used to
produce an eye diagram. An eye diagram is useful as it
provides a qualitative view of peak−to−peak deterministic
jitter. To form an eye diagram, a PRBS (Pseudo−Random Bit
Sequence) signal is sent to the DUT input, and the DUT
output (the eye diagram) is observed on the oscilloscope.
The NBSG14 eye diagram in Figure 41 was created by an
Advantest D3186 generating a 2³¹âˆ’1 PRBS data pattern at
10.8 Gbps. The Tektronix TDS8000 oscilloscope with an
80E01 50 GHz sampling module acquired 7000 samples.
The total deterministic jitter represented by the histogram at
the top left of the eye diagram is 18.00 ps peak−to−peak. As
deterministic jitter increases, the eye closes (i.e., the eye
width decreases) which increases the probability of a data
transmission error.
Pattern Generator
PRBS
DUT
PRBS
Trigger
Oscilloscope
DJ (PP)
Total Jitter(DJ) + Pattern Generator (DJ) ) DUT (DJ) ) Oscilloscope (DJ)
Figure 40. Total Deterministic Jitter Test
Figure 41. Total Deterministic Jitter Eye Diagram
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