opening seen at the output signal of a device is within specifications,
that is, within certain timing and voltage limits.
Measuring the eye openings with an oscilloscope used to be a time-
consuming procedure. With the Fast Eye Mask measurement of the
Serial BERT, pass/fail information can be obtained within seconds.
This is achieved by measuring the bit error rate at a limited number of
test points. Up to 32 measurement points can be specified, each defined
by a sampling time relative to the actual sampling point (which can be
the optimum sampling point) and a threshold voltage (which is
adaptive). In practice, six measurement points will often suffice to
approximate the shape of the eye. Six measurement points are preset
by default.
N O T E
The Fast Eye Mask can be run by using the appropriate SCPI commands, making it
possible to integrate the Serial BERT into a testing environment. See the
Programming Guide for details.
Example Results
The Fast Eye Mask measurement measures the bit error rate at certain
measurement points. These points have to be positioned inside the
expected eye opening.
The results of a Fast Eye Mask measurement are displayed in numerical
form:
5
Advanced Analysis
242
Agilent J-BERT N4903 High-Performance Serial BERT
Summary of Contents for J-BERT N4903
Page 1: ...S Agilent J BERT N4903 High Performance Serial BERT User Guide s Agilent Technologies...
Page 68: ...2 Setting up Patterns 68 Agilent J BERT N4903 High Performance Serial BERT...
Page 158: ...4 Setting up the Error Detector 158 Agilent J BERT N4903 High Performance Serial BERT...
Page 314: ...6 Evaluating Results 314 Agilent J BERT N4903 High Performance Serial BERT...
Page 374: ...7 Jitter Tolerance Tests 374 Agilent J BERT N4903 High Performance Serial BERT...
Page 394: ...8 Solving Problems 394 Agilent J BERT N4903 High Performance Serial BERT...
Page 434: ...Index 434 Agilent J BERT N4903 High Performance Serial BERT...
