The HP/Agilent 34902A is a 16-channel multiplexer module that extends the measurement capabilities of Agilent 34970A and 34972A Data Acquisition/Switch Units. Built around reed relay switching technology, this module enables both 2-wire and 4-wire measurement configurations on the same card, delivering scan rates up to 250 channels per second. The flexible channel architecture accommodates mixed measurement topologies, making it suitable for automated test environments requiring high-throughput data acquisition and signal monitoring across multiple inputs.
Technical Specifications
• Channels: 16 multiplexed inputs
• Switching Technology: Reed relays
• Scan Rate: Up to 250 channels/second
• Maximum Voltage per Channel: 300 V
• Maximum Current per Channel: 50 mA
• Configuration Modes: Mixed 2-wire and 4-wire on single module
• Thermocouple Reference: Built-in junction
– Key Features
• Reed relay-based switching provides reliable, high-speed multiplexing without contact wear concerns typical of electromechanical alternatives
• Mixed-mode channel configuration allows simultaneous 2-wire voltage/resistance measurements and 4-wire resistance or current measurements
• Integrated thermocouple cold-junction compensation simplifies temperature measurement setup
• Current measurement capability via user-supplied shunt resistors provides measurement flexibility
• Single-slot module integration into host mainframe minimizes footprint impact
– Typical Applications
• Automated electrical characterization of multi-pin components and assemblies
• Temperature and voltage monitoring across distributed sensor arrays
• High-channel-count data logging with mixed measurement types
• Production test environments requiring fast channel switching and mixed signal routing
– Compatibility & Integration
The 34902A installs directly into available module slots on Agilent/Keysight 34970A or 34972A mainframes. Mainframe firmware and software handle all multiplexer control, sequencing, and data formatting automatically. Shunt resistor selection for current measurements remains operator-configurable based on measurement range requirements.
