Keysight / Agilent / HP E1459A 64-Channel Isolated Digital Input/Interrupt Module

The Keysight E1459A is a register-based VXI module delivering 64 channels of optically isolated digital input with interrupt capability. Housed in a C-size, 1-slot form factor, it senses DC levels and edge transitions up to 48 Vdc across four selectable input voltage ranges: 5 Vdc, 12 Vdc, 24 Vdc, and 48 Vdc. Each channel provides optical isolation rated to 125 Vrms or Vdc, protecting against common-mode voltages between channels or between any terminal and chassis. The module accepts maximum channel input voltages of 60 Vdc and features TTL-compatible logic levels at 5 V maximum.

– Technical Specifications

• Channel Configuration: 64 isolated digital input channels
• Input Voltage Ranges: 5 Vdc, 12 Vdc, 24 Vdc, 48 Vdc
• Input Thresholds: Min: 1 Vdc, 2.5 Vdc, 7 Vdc, or 14 Vdc; Max: 4 Vdc, 9.5 Vdc, 17 Vdc, or 31 Vdc
• Input Current (Typical): 0.5 mA, 1.3 mA, 2.8 mA, or 5.8 mA at nominal voltages
• Maximum Channel Voltage: 60 Vdc (High to Low)
• Isolation Voltage Rating: 125 Vrms or Vdc
• Pull-up Resistance: 9.4 kΩ effective with onboard 5 V supply
• Debounce Range: 16 µs to 1074 s in binary increments, independently programmable for channels 1-32 and 33-64
• VXI Interface: Register-based, A16, slave only
• Typical Read Time: 1 ms per 16-bit word
• Terminals: Removable screw-type; maximum wire size 16 AWG

– Key Features

• Programmable debounce filtering for noise rejection and signal conditioning
• Strobe-in, ready-for-data, and interrupt-out handshake lines per 16-bit word
• Parallel strobe-in connection capability for 32-bit or 64-bit data transfers
• Open/closed switch detection via onboard 5 V pull-up supply

– Typical Applications

• Industrial automation and process control monitoring
• Automated test equipment (ATE) signal acquisition
• Discrete event logging in demanding electrical environments
• Multi-channel switch state detection and edge-triggered interrupt handling

– Compatibility & Integration

Designed for integration into VXIbus systems. Connects via P1/P2 VXI connectors with register-based slave operation. The module operates as a non-master device within the VXI architecture.