Keysight / Agilent / HP E1533A 16-Bit Digital I/O SCP

The Keysight E1533A is a 16-bit Digital I/O Signal Conditioning Plug-on (SCP) module for VXI mainframe systems. It provides TTL-compatible digital input and output lines organized into two independent 8-bit channels, each independently configurable as input or output ports. The module integrates directly into compatible VXI cards to deliver reliable digital interfacing for automated test and data acquisition applications.

## Technical Specifications

**Digital I/O Architecture:**
• 16 TTL-compatible input/output lines
• Two independent 8-bit channels
• Each channel independently configurable as input or output port
• Passive (resistor) pull-up option for output ports
• Active (transistor) pull-up option for output ports

## Key Features

Flexible channel configuration allows each 8-bit port to operate independently as either source or load. Dual pull-up options—passive resistor and active transistor—provide design flexibility for different impedance and drive requirements. The SCP form factor enables modular integration into existing VXI infrastructure without requiring significant system redesign.

## Typical Applications

The E1533A serves digital control, sensing, and switching applications within automated test environments. It is suitable for synchronizing external instruments, commanding relay matrices, reading discrete sensor states, and interfacing with TTL-level logic circuits in data acquisition systems.

## Compatibility & Integration

The E1533A is designed for use with specific Keysight/Agilent VXI cards: E1313A, E1413A/B, E1415A, E1419A, and E1422A. The E1313A can accommodate up to four SCP modules; other compatible cards support up to eight modules. Signal Conditioning Plug-ons such as the E1533A were originally offered as options for E1313A and E1413A/B VXI cards and integrate with Scanning A/D systems to provide comprehensive signal conditioning across multiple input channels.