Agilent/Keysight U2651A

The Keysight U2651A is a USB modular isolated digital input/output device that delivers 32 isolated digital input channels and 32 isolated digital output channels - 64 opto-isolated digital lines total. It connects via USB 2.0 with USBTMC-USB488 standard support and operates standalone or within a modular chassis system. The device provides 1250 Vrms transient isolation protection, handles input voltages from 10 to 24 V, and supports output voltages up to 35 V maximum.

An on-board isolated +5 V supply simplifies testing and integration. Windows-compatible with SCPI and IVI-COM command support, the U2651A integrates with Keysight VEE, MATLAB, LabVIEW, and Visual Studio environments. Bundled Keysight Measurement Manager software and BenchVue enablement streamline setup and data logging.

Technical Specifications

• Digital channels: 32 input, 32 output (64 opto-isolated lines total)


• USB interface: USB 2.0 (480 Mbps)


• Isolation: 1250 Vrms transient protection


• Input voltage range: 10 to 24 V DC


• Output voltage: up to 35 V maximum


• External supply voltage: 5 to 35 V (for external loads)


• On-board isolated supply: +5 V


• Power consumption: +12 VDC, 260 mA maximum


• Connector: 100-pin SCSI-II


• Dimensions: 120 × 182.40 × 44 mm (with casing); 105 × 174.54 × 25 mm (without casing)


• Weight: 565 g (with casing)


• Operating temperature: 0 to +55 °C


• Storage temperature: –20 to 70 °C

Key Features

• Virtual Port grouping: Assign any eight input/output bits to a single virtual port for simultaneous operations


• Interrupt function: Automatic triggering on digital state change


• Command logger: Captures configuration commands and exports as code snippets


• SCPI and IVI-COM support for standardized instrument control


• Standalone or modular chassis deployment options

Typical Applications

• Industrial control and process monitoring


• Data acquisition systems requiring galvanic isolation


• Digital signal routing and switching


• Real-time event capture and triggering

Compatibility & Integration Supported development environments: Keysight VEE, MATLAB R2007a, NI LabVIEW, Microsoft Visual Studio, Visual Studio .NET, C/C++, and Visual Basic 6. Compliant with CE marking, WEEE Directive (2002/96/EC), IEC 61326-1:2002, and tested to IEC/EN 60068-2 (Shock and Vibration).