Agilent/Keysight U5491A

The Keysight U5491A is a PCIe digitizer card engineered for demanding signal acquisition and analysis in research, development, and production environments. This single-slot, full-length card delivers 10-bit ADC resolution with sampling rates up to 10 GS/s in single-channel mode and 5 GS/s in dual-channel configuration. An integrated Xilinx FPGA enables real-time signal processing, noise reduction, and pulse analysis of sub-nanosecond transients across a DC to 2.5 GHz analog bandwidth.

Technical Specifications

• ADC Resolution: 10-bit


• Sampling Rate: Up to 5 GS/s (dual-channel); up to 10 GS/s (single-channel with interleaving)


• Analog Bandwidth: DC to 2.5 GHz


• On-Board Memory: Up to 4 GB DDR3


• Input Impedance: 50 Ω


• Input Full Scale Range: Selectable 250 mV to 5 V


• Input Voltage Offset Range: ±0.5x FSRmax


• Host Interface: PCI Express 2.0

Key Features

• Real-Time Signal Processing: Integrated FPGA with selectable firmware modes including digitizer (DGT), real-time averaging (AVG), noise-suppressed accumulation (NSA), and continuous simultaneous acquisition and readout (-CST option)


• Noise Reduction: Real-time sampling and accumulation from 1 to 16,384 triggers improves signal-to-noise ratio and dynamic range


• Channel Interleaving: Combines two channels to achieve 10 GS/s sampling while maintaining measurement fidelity


• Pulse Analysis: Optimized architecture for sub-nanosecond pulse characterization


• Dynamic Range Performance: Excellent SFDR and SNR at high frequencies, particularly at 250 mV full-scale range


• Self-Trigger Mode: Autonomous triggering capability for autonomous data capture

Typical Applications

• High-speed signal acquisition and waveform analysis


• Pulse and transient characterization


• Noise-sensitive measurement systems requiring real-time averaging


• Multi-gigahertz bandwidth testing and verification

Compatibility & Integration

• Software: Keysight IO Libraries Suite support


• Operating Systems: Windows and Linux


• Environmental Rating: Type tested per Keysight Environmental Test Manual, IEC 60068-2, and MIL-PRF-28800F Class 3