Agilent/Keysight 81250A – ParBERT Platform Mainframe

The Agilent/Keysight 81250A is a modular parallel bit error ratio tester (BERT) platform engineered for characterization of high-speed multi-port devices across computing, telecommunications, and semiconductor applications. Built on a VXI mainframe architecture, the system accommodates plug-in modules for flexible, scalable configurations. It performs both electrical and optical signal generation and analysis across data rates from 675 Mbit/s to 45 Gbit/s.

Technical Specifications

• 675 Mbit/s, 1.65 Gbit/s, 2.7 Gbit/s, 3.35 Gbit/s, 7 Gbit/s, 10.8 Gbit/s, 13.5 Gbit/s, 45 Gbit/s (via dedicated modules) Clocking and Timing:


• External clock input: up to 10.8/21.6 GHz


• Central clock modules include E4805B (675 MHz), E4808A (high performance), and E4809A (13.5 GHz)


• Example timing (E4866A 10.8 Gb/s generator): data range 9.5–10.8 Gbit/s, clock range 9.5–10.8 GHz, delay range 0–300 ns, delay resolution 1 ps, accuracy ±20 ps ±50 ppm relative to zero-delay


• Module skew: typically 50 ps after deskewing for same-type modules at unchanged system frequency


• Delay control input for jitter generation


• Sub-rate clock outputs available Pattern Generation and Analysis:


• Pseudo-Random Word Sequences (PRWS), PRBS, and user-defined patterns on parallel lines


• Memory-based patterns: 256-bit segment length resolution, up to 33,554,432 bits


• Multi-level signal generation via internal digital and analog channel add functions


• Pattern sequencing for data flow control (single, looped, infinite)


• Event handling for real-time control with external signal integration (stop/go, loop control, error triggering)


• Bit error ratio analysis with user-defined, PRBS/PRWS, or mixed data System Architecture:


• Master-slave clock configurations for synchronized multi-frame operation


• Clock Data Recovery (CDR) available in select modules (e.g., 45 Gb/s DeMUX)


• Multiple clock groups supporting asynchronous or synchronized operation

Key Features

• Modular VXI mainframe design for scalable single-module to multi-mainframe configurations


• Multi-port parallel testing capability


• Electrical and optical signal support


• Flexible clocking with external inputs to 21.6 GHz

Typical Applications

• High-speed device characterization in computer and telecommunications sectors


• Semiconductor test and validation


• Multi-port parallel data path verification


• Jitter and timing analysis

Compatibility & Integration The platform integrates dedicated plug-in modules for specific data rates and functions. Clock synchronization across multiple frames enables large-scale parallel test systems. Event-triggered logic supports integration with automated test environments.