The Keysight N4901A is a high-performance serial Bit Error Rate Tester (BERT) engineered for characterization and validation of high-speed digital communication systems across 150 Mb/s to 13.5 Gb/s. The instrument combines precision pattern generation, integrated Clock Data Recovery, and advanced jitter analysis to support both R&D and manufacturing test environments.
Technical Specifications
Performance Metrics
• Frequency Range: 150 Mb/s to 13.5 Gb/s
• Intrinsic Jitter: < 1 ps RMS (typical)
• Jitter Modulation: 200 ps, DC to 1 GHz
• Transition Time (10%-90%): < 25 ps
• Input Sensitivity: < 50 mV pp
• Input Voltage Window: -250 mV to +250 mV
• Decision Threshold Range: -2 V to 3 V
Pattern Generation
• PRBS Sequences: 2ⁿ-1 for n = 7, 10, 11, 15, 23, 31
• Zero Substitution: 2ⁿ for n = 7, 10, 11, 13, 15, 23
• Variable Mark Density: 1/8, ¼, ½, ¾, 7/8 at 2ⁿ for n = 7, 10, 11, 13, 15, 23
• User-Programmable Patterns: 1 bit to 33,554,432 bits (2²⁵)
• Generation Range (Internal/External Clock): 620 Mb/s to 13.5 Gb/s
• Signal Amplitude: 0.1 Vpp to 1.8 Vpp
• Signal Offset: -2 V to 3 V
• Differential Support: LVDS
Clock Data Recovery (CDR)
• Operating Bands: 1.0–1.6 Gb/s, 2.11–3.20 Gb/s, 4.23–6.40 Gb/s, 9.9–10.9 Gb/s
• Typical Bandwidth at 9.90–10.9 Gb/s: 6.0 MHz
• Typical Bandwidth at 4.23–6.40 Gb/s: 3.6 MHz
• Typical Bandwidth at 2.12–3.20 Gb/s: 1.8 MHz
– Key Features
• Bathtub curve and eye contour analysis
• Q-factor output level measurement
• Timing measurements: RJ/DJ separation, setup/hold time, phase margin, total jitter
• Fast eye mask measurement (~1 second)
• Spectral decomposition of jitter
• Error location capture
• Block Error Mode and Bit Error Mode for selective BER measurements
– Electrical & System Requirements
• Power Consumption: Maximum 350 VA (all options installed)
• Power Input: 100–240 V AC, 47–63 Hz, single-phase with auto-ranging
• Output/Input Termination: 50 Ω required for unused connectors
– Compatibility & Integration
Remote control via LAN, USB, or GPIB interfaces enables integration into automated test systems and bench-top configurations.
