The Agilent/HP 44474A Rev B is a 16-bit digital I/O module card for the 3499A/B/C mainframe family, delivering flexible data acquisition and control in industrial and laboratory environments. It provides 16 bi-directional data lines plus 4 control/handshaking lines with independent addressing by individual bits, 8-bit ports, or 16-bit word. Each I/O line sinks up to 0.125 A from external devices, making it suitable for direct interfacing with industrial logic and sensor networks.
Technical Specifications
• Digital I/O Lines: 16 bi-directional with individual, 8-bit port, or 16-bit word addressing
• Control/Handshaking Lines: 4 dedicated lines
• Input Levels (TTL): Vin (high) > 2.0 V; Vin (low) 2.4 V @ I < 8 mA; Vout (low) < 0.4 V @ I 2.4 V @ I < 400 µA; Vout (low) < 0.5 V @ I < 2 mA
• Current Sink Capability: Up to 0.125 A from external devices at Vout < 1.25 V
• Maximum Line Voltage (Digital I/O): +30 V DC
• Maximum Line Voltage (Handshake): +5 V DC
• Connector: Screw terminals included; optional HP 44484A terminal block
– Key Features
• TTL-compatible input and open-collector output architecture
• Flexible addressing—select individual bits, dual 8-bit ports in mixed I/O mode, or single 16-bit word
• High current sink capability enables direct control of relays, solenoids, and indicator lamps
• Independent port configuration supports simultaneous input and output operations
• Accommodates ±30 V transients on digital lines for industrial noise immunity
– Typical Applications
• Automated test equipment (ATE) with distributed I/O control
• Sensor and switch interfacing in data acquisition systems
• Relay and solenoid driving in laboratory automation
• Mixed-signal control systems requiring independent input/output channels
– Compatibility & Integration
Installs directly into Agilent/HP 3499A, 3499B, and 3499C mainframes. User's Manual, Service Manual, and Quick Reference Guide for the 3499A/B/C platform available.
