Keysigth Technologies N4903B J-BERT
dataTec ▪ Ferdinand-Lassalle-Str. 52 ▪ 72770 Reutlingen ▪ Tel. 07121 / 51 50 50 ▪ Fax 07121 / 51 50 10 ▪ info@datatec.de ▪ www.datatec.de
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07 | Keysight | J-BERT N4903B High-Performance Serial BERT, 7 Gb/s and 12.5 Gb/s - Data Sheet
ser Interface and Measurement Suite
uic eye diagram and masing
The uic eye diagram allows a one-shot chec for a valid signal.
Due to the higher sampling depth of a BERT, the eye contour
lines visualize the measured eye at a deeper BER level for more
accurate results. Extrapolated eye contour lines display the eye
opening for even lower BER levels such as 10-15 reducing the
measurement time signicantly. The display shows numerical
results for 1- and 0- level eye amplitude and width total jitter
and more. Eye mass can be loaded from a library. iolations of
the captured eye mas are displayed. The result screen can be
printed and saved for documenting the test results see igure 6.
igure 6. uic eye diagram with BER contour and masing
Spectral jitter decomposition
The spectral jitter decomposition measures the spectral
decomposition of jitter components. hen debugging designs
the jitter decomposition simplies identifying deterministic jitter
sources (see Figure 7).
igure 7. Spectral jitter decomposition for debugging jitter sources in a design
Eye contour
The eye opening is a ey characteristic of a device. The BER is
displayed as a function of sampling delay and sampling threshold.
Different views are available eye contour see igure 8 pseudo
colors and eual BER plots.
igure 8. Eye contour with colors indicating BER level
BERT scan including RJ/DJ separation
This measurement shows the BER versus the sampling point
delay which is displayed as a bathtub curve or as a histogram.
The measurement results are displayed in a table with setup and
hold time over phase margin total jitter in rms or pea-to-pea
and random and deterministic jitter. The measurement method is
euivalent to IEEE 802.3ae see igure 9.
igure 9. BERT scan including RJ/DJ separation total jitter