Renesas IS82C55AZ96

Overview

IS82C55AZ96 from Intersil is a CMOS Programmable Peripheral Interface (PPI) IC designed for parallel I/O expansion in 8-bit microprocessor systems such as 80C86/80C88. It provides 24 programmable I/O pins across three 8-bit ports (A, B, C), supports three operational modes (Mode 0–2), delivers 2.5mA drive capability per pin, and operates at up to 8MHz with no wait states. It is used in industrial control panels for direct peripheral interfacing without external logic.

For engineers reviewing the IS82C55AZ96 datasheet, IS82C55AZ96 pinout, IS82C55AZ96 application, or IS82C55AZ96 equivalent, key selection criteria include its TTL-compatible 5V operation, bus-hold circuitry eliminating pull-up resistors, direct bit set/reset on Port C, enhanced control word read capability, and compatibility with legacy 8255A-based designs requiring low-power CMOS upgrade.

Technical Context

The IS82C55AZ96 implements a static CMOS architecture with self-aligned silicon gate process (Scaled SAJI IV), enabling low standby current (10μA) while maintaining full TTL compatibility across –40°C to +85°C. Its internal control logic decodes A0/A1 address lines with RD/WR/CS to select Port A, Port B, Port C, or the control register - supporting both mode configuration and single-bit manipulation of Port C.

Port grouping follows Group A (Port A + Port C upper 4 bits) and Group B (Port B + Port C lower 4 bits), each with dedicated control blocks that interpret mode-setting control words. Mode 2 enables bidirectional bus operation exclusively on Port A using five dedicated Port C lines (PC3–PC7) for ACK, STB, IBF, OBF, and INTR signaling - all managed via hardware flip-flops and bit-set/reset commands.

Key Specifications

Pinout & Package

IS82C55AZ96 is supplied in a 44-lead plastic leaded chip carrier (PLCC) package with Pb-free finish (RoHS compliant), per ordering code IS82C55AZ96.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable peripheral interface applications.

Compared with Intel 8255A-5 and IS82C55A-5Z, IS82C55AZ96 uniquely combines industrial temperature rating, Pb-free RoHS compliance, bus-hold circuitry, and 8MHz operation - making it the only option qualified for new designs requiring reliability, regulatory compliance, and power efficiency in harsh environments.

Availability

IS82C55AZ96 is available at Aetrix Electronics and suitable for industrial PLCs, legacy microprocessor upgrades, embedded keypad interfaces, and multi-channel data acquisition systems requiring stable component supply and long-term manufacturability.

Supply support for IS82C55AZ96 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Intersil Corporation was a U.S.-based semiconductor company specializing in high-performance analog and mixed-signal ICs, later acquired by Renesas Electronics in 2017.

The IS82C55AZ96 belongs to Intersil's legacy CMOS peripheral interface product line, engineered to provide pin-compatible, low-power upgrades to industry-standard 8255A-based systems in industrial control and embedded computing.

FAQ

What is the operating temperature range for the IS82C55AZ96?

The IS82C55AZ96 is specified for operation from –40°C to +85°C, qualifying it for industrial-grade applications including factory automation, outdoor instrumentation, and transportation control systems. This extended temperature range distinguishes it from commercial-grade variants like IS82C55A-5Z (0°C to +70°C) and confirms its suitability for environments with significant thermal cycling or ambient extremes.

Does the IS82C55AZ96 require external pull-up resistors on its I/O pins?

No, the IS82C55AZ96 integrates bus-hold circuitry on all I/O ports (PA0–PA7, PB0–PB7, PC0–PC7), which actively maintains un-driven pins at their last valid logic state with ≤400μA hold current. This eliminates the need for external pull-up or pull-down resistors in CMOS-based designs, reducing bill-of-materials cost and PCB routing complexity while improving noise immunity.

Can the IS82C55AZ96 be used as a direct replacement for the NMOS 8255A in existing designs?

Yes, the IS82C55AZ96 is explicitly designed as a pin-compatible and functionally equivalent CMOS replacement for the NMOS 8255A. It retains identical pinout, control signal behavior, mode definitions, and register mapping. Engineers can substitute IS82C55AZ96 without modifying PCB layout or firmware - gaining benefits including lower power consumption, higher speed (up to 8MHz), and built-in bus-hold functionality.

How does the IS82C55AZ96 handle interrupt generation in Mode 1 or Mode 2?

The IS82C55AZ96 generates hardware interrupts via INTRA and INTRB outputs using dedicated INTE flip-flops controlled by bit set/reset operations on Port C (PC4 for INTE A, PC2 for INTE B). In Mode 1, INTRA asserts when STB=1, IBF=1, and INTE=1; in Mode 2, a single INTRA line supports bidirectional interrupt requests. All interrupt conditions are cleared automatically on RD or WR falling edge, enabling clean, deterministic CPU service routines.

What packaging and compliance standards apply to the IS82C55AZ96?

The IS82C55AZ96 is supplied in a 44-lead plastic leaded chip carrier (PLCC) package with Pb-free (RoHS-compliant) finish, per Intersil's "Pb-Free Plus Anneal" specification. It meets IPC/JEDEC J-STD-020 moisture sensitivity level (MSL) requirements for Pb-free reflow profiles and uses 100% matte tin plating on terminations - ensuring compatibility with both SnPb and Pb-free soldering processes in high-reliability manufacturing.