IS82C55AZ

Overview

The IS82C55AZ is a CMOS Programmable Peripheral Interface (PPI) manufactured by Renesas Electronics Corporation. It serves as a high-performance, static CMOS version of the industry-standard NMOS 8255A. The device features 24 programmable I/O pins organized into three 8-bit ports (Port A, Port B, and Port C), which can be individually programmed into two groups of 12 bits. It supports parallel interface communication with a maximum clock frequency of 8 MHz and operates on a single 5V power supply ranging from 4.5 V to 5.5 V. The component includes interrupt output capability and is housed in a 44-pin PLCC package.

Feature Summary

• Fully TTL compatible across commercial, industrial, and military temperature ranges without requiring external pull-up resistors due to integrated bus hold circuitry.
• High-speed operation with no wait states required for 80C86 and 80C88 microprocessors, ensuring efficient data transfer.
• Provides direct bit set/reset capability for individual I/O lines and enhanced control word read functionality for system monitoring.

Applications

• Interface solutions for 80C86 and 80C88 microprocessor-based systems
• General-purpose programmable I/O expansion in embedded controllers
• Industrial control systems requiring robust TTL-compatible peripheral interfacing

Procurement Notes

Verify the specific suffix 'AZ' against the manufacturer's current datasheet to confirm it denotes the industrial temperature range (-40°C to +85°C) and lead-free/plated finish status. Confirm the 44-PLCC package availability and check for any recent Product Change Notifications (PCN) regarding moisture sensitivity levels or manufacturing site changes before finalizing procurement plans.

Selection Notes

Select the IS82C55AZ when a static CMOS replacement for the NMOS 8255A is required to reduce power consumption while maintaining pin compatibility. Ensure the design requires a 44-pin surface-mount package and an 8 MHz maximum clock speed. Verify that the application needs interrupt generation capabilities and operates within the specified 4.5 V to 5.5 V voltage range.

Part Context

The IS82C55AZ belongs to the 82C55A family of programmable peripheral interfaces. This series represents the CMOS evolution of the classic 8255A, offering lower power dissipation and higher speed. It is designed to be pin-compatible with its NMOS predecessor, facilitating easy upgrades in existing designs to improve performance and reduce thermal requirements.

Replacement Considerations

The IS82C55AZ is functionally equivalent to the Intel 82C55A and other CMOS variants like the 82C55AP. For direct pin-compatible replacements, consider other manufacturers' CMOS 8255A clones. Verify that substitute components support the same 44-PLCC package and meet the 8 MHz timing requirements.