HP / Agilent 81250 13.5 Gb/s ParBERT Modules (N4872A, N4873A)

The HP/Agilent 81250 ParBERT N4872A and N4873A modules deliver integrated transmit and receive capability for high-speed serial link characterization up to 13.5 Gb/s. The N4872A generator produces differential and single-ended NRZ signals with output amplitude 0.1 Vpp to 1.8 Vpp and transition times below 20 ps. The N4873A analyzer detects signals with 50 mVpp input sensitivity and 25 ps minimum pulse width resolution. Together, these VXI modules enable BERT testing of SerDes devices, multiplexers, and communication standards across the 620 Mb/s to 13.5 Gb/s range.

## Technical Specifications

**N4872A Generator Module**
• Data rate: 620 Mb/s to 13.5 Gb/s
• Output amplitude: 0.1 Vpp to 1.8 Vpp (5 mV resolution)
• Transition time (20%-80%): <20 ps
• Jitter: <9 ps peak-to-peak (typical)
• Jitter modulation bandwidth: DC to 1 GHz
• External clock input: 620 MHz to 13.5 GHz
• Crosspoint adjust: 20% to 80%
• Delay line: voltage controllable, up to 200 ps peak-to-peak jitter

**N4873A Analyzer Module**
• Data rate: 620 Mb/s to 13.5 Gb/s
• Minimum detectable pulse width: 25 ps (typical)
• Input sensitivity: 50 mVpp typical at 10 Gb/s PRBS 2³¹-1, BER 10⁻¹²
• Phase margin: 1 UI – 12 ps (typical)

## Key Features

• Generates PRBS patterns up to 2³¹-1 and user-defined patterns to 64 Mb
• Three synchronization methods: bit-by-bit shift, word detect, adjustable sampling delay to 10 ns
• Pattern sequencer with looping and event branching
• Supports parallel-to-serial, serial-to-parallel, and serial-to-serial test configurations
• Modular design fits single VXI slot per module

## Typical Applications

• SerDes device characterization and stress testing
• Multiplexer and demultiplexer validation
• Communication standard compliance testing
• High-speed signal integrity analysis

## Compatibility & Integration

Operates as VXI modules within the 81250 ParBERT platform, which supports data rates from 675 Mb/s to 45 Gb/s system-wide.