Keysight / Agilent / HP 34522 Digital I/O Module

The Keysight 34522 Digital I/O Module is a plug-in expansion module that adds digital input/output capability to compatible Keysight data acquisition systems. It provides 32 bi-directional TTL-compatible data lines, 8 edge-triggered interrupt lines, and 16 high-power FET outputs for controlling external devices. The module supports read/write rates exceeding 40 kHz and integrates into 34970A and 34972A mainframes.

## Technical Specifications

• **Digital Data Lines:** 32 bi-directional TTL-compatible lines
• **Port Configuration:** Four independent 8-bit ports with dedicated handshake lines; ports can operate individually or combine for 16-bit or 32-bit parallel transfers
• **Interrupt Capability:** 8 edge-triggered interrupt lines for external event signaling
• **High-Power Outputs:** 16 FET outputs for driving higher-power external loads
• **Data Rate:** Read/write rate exceeding 40 kHz
• **Physical Weight:** Approximately 2 lbs

## Key Features

• TTL-level logic on all 32 data lines ensures direct compatibility with standard digital devices
• Flexible port architecture accommodates both narrow (8-bit) and wide (16/32-bit) parallel data operations
• Edge-triggered interrupt structure supports efficient external event handling
• High-power FET output stage eliminates the need for external driver stages when interfacing with industrial loads
• Compact plug-in form factor minimizes mainframe footprint

## Typical Applications

This module suits applications requiring parallel digital communication, such as equipment control, sensor interface bridging, and event-driven data acquisition workflows where TTL signaling is appropriate.

## Compatibility & Integration

The 34522 installs directly into Keysight 34970A and 34972A Data Acquisition/Switch Unit mainframes. Its modular design allows mixed installations with other plug-in modules within the same chassis.