81250 Datasheet, PDF (39/64 Pages) Keysight Technologies – Agilent ParBERT 81250 Parallel Bit Error Ratio Tester

Table 44. E4861B analyzer timing all timing parameters are measured at ECL levels, terminated
with 50 Ω to GND
Sampling rate
Sample delay
Start delay range
Fine delay range
Resolution
Accuracy
Skew
20.834 MHz to 3.350 GHz
Same as delay = start delay + fine delay
Can be specified as leading edge delay in fraction
of bits in each channel
0 to 200 ns (not limited by period)
±1 period (can be changed without stopping)
1 ps
±25 ps ±50 ppm relative to the zero-delay and
temperature change within ±10 °C after
autocalibration
50 ps typ. after deskewing at customer levels and
unchanged system frequency
Table 45. E4861B pattern and sequencing
Patterns
Memory based
PRBS/PRWS
Mark density
Errored PRBS/PRWS
Extended ones or zeros
Clock patterns
Analyzer
auto-synchronization
Up to 16 Mbit
2ⁿ - 1, n = 7, 9, 10, 11, 15, 23, 31
1/8, 1/4, 1/2, 3/4, 7/8 at 2ⁿ - 1, n = 7, 9, 10, 11, 15
2ⁿ - 1, n = 7, 9, 10, 11, 15
2ⁿ - 1, n = 7, 9, 10, 11, 15
Divide or multiply by 1, 2, 4
On PRBS or memory-based data
Manual or automatic by:
Bit synchronization(1) with or without automatic
phase alignment. Automatic delay alignment
around a start sample delay (range: ± 10 ns)
BER threshold: 10^-4 to 10^-9
(1) With PRBS data, analyzers can autosyncronize on incoming PRBS data bits. When using
memory-based data, this data must contain a unique 48 bit detect word at the beginning of the
segment, and the generators must be on a separate system clock. “Don’t cares” within detect
word are possible. If several inputs synchromize, the delay diffference between terminals must
be smaller than ±5 segment length resolution.
ParBERT 81250 Main Overview
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