Agilent/Keysight U2355A

The Keysight U2355A is a USB modular multifunction data acquisition device that combines analog input, analog output, digital I/O, and counter functionality in a compact form factor. It delivers 16-bit resolution analog acquisition across up to 64 single-ended or 32 differential input channels at sampling rates to 250 kSa/s, paired with two 12-bit analog outputs operating at 1 MSa/s update rate. The device integrates 24-bit programmable TTL digital I/O, two general-purpose counter channels, and 8M points of onboard memory to support polling, continuous, and burst acquisition modes.

Technical Specifications

• 64 single-ended or 32 differential channels


• 16-bit resolution


• Up to 250 kSa/s sampling rate


• AC/DC input coupling


• 1 MΩ ±5% || 15 pF ±10% input impedance (standard); >10 MΩ (high impedance mode) -# Analog Output


• 2 channels


• 12-bit resolution


• Up to 1 MSa/s update rate -# Digital I/O


• 24-bit programmable TTL channels -# Digital Counters


• 2 general-purpose channels -# Performance


• 8M points onboard memory


• Polling, continuous, and burst acquisition modes -# Interfaces


• USB 2.0, USBTMC-USB488 compliant -# Physical Characteristics


• 182.4 mm × 120 mm × 44 mm


• 565 g


• Operating temperature: 0°C to +55°C

Key Features

• Flexible channel configuration balances single-ended and differential measurement needs


• High input impedance option minimizes loading effects on sensitive sources


• Dual analog outputs enable stimulus-response testing and closed-loop applications


• Programmable digital I/O supports TTL-level signal control and monitoring

Typical Applications Industrial data logging, R&D measurement campaigns, sensor characterization, real-time signal monitoring, and hardware-in-the-loop testing.

Compatibility & Integration Operates with Microsoft Windows platforms. Supports Keysight VEE, MATLAB R2007a and later, NI LabVIEW, Microsoft Visual Studio, and Keysight Measurement Manager (AMM). Integrates into the U2781A USB modular chassis for expanded system configurations. Terminal block accessories U2901A and U2902A, plus U2802A thermocouple module, extend measurement capabilities.