Agilent/Keysight 44423A

The Agilent/Keysight 44423A is a 20-channel FET multiplexer that routes signals in automated test systems and precision measurement applications. Each of its 20 channels contains three relays—High, Low, and Guard lines—organized into two groups of 10. The multiplexer supports flexible switching modes: one channel per decade closure, random channel selection, or incremental stepping between programmable limits. Simultaneous closure of two channels (one per decade) enables four-terminal resistance measurements. Its low thermal offset characteristics make it ideal for precision transducer and temperature-sensor measurements where signal integrity and measurement accuracy are critical.

– Technical Specifications

• Channel Configuration: 20 channels organized into two groups of 10
• Relay Configuration: Three relays per channel (High, Low, Guard lines)
• Switching Modes: Single channel per decade; random or incremental channel closure between programmable limits
• Simultaneous Operation: Two channels closeable at once (one per decade), enabling four-terminal measurements
• Thermal Performance: Low thermal offset for precision low-level measurements
• Physical: 15 × 8 × 3 inches, 2 lbs

– Key Features

• Multi-mode switching for flexible signal routing in automated test environments
• Guard line capability on each channel for noise rejection and signal integrity
• Programmable channel sequencing with random and incremental stepping options
• Four-terminal measurement support for accurate impedance and resistance characterization

– Typical Applications

• Transducer and sensor signal multiplexing
• Temperature measurement systems requiring low thermal offsets
• Precision resistance and impedance measurement via four-terminal configuration
• Automated test systems with multi-channel signal routing requirements

– Compatibility & Integration

The 44423A is designed as an option for the 3497A Data Acquisition/Switch Unit, integrating directly into mainframe-based test systems.