CQ82C55A

Overview

The CQ82C55A is a CMOS Programmable Peripheral Interface manufactured by Renesas Electronics Corporation. It provides 24 programmable I/O pins organized into three 8-bit ports (Port A, Port B, and Port C). The device supports parallel interface communication with microprocessors and features open-drain outputs capable of sourcing or sinking 2.5mA. It operates within a supply voltage range of 4.5V to 5.5V and functions at temperatures between 0°C and 70°C. The component is housed in a 44-MQFP package measuring 10x10 mm.

Feature Summary

• Provides 24 individually programmable I/O pins divided into two groups of 12 for flexible configuration
• Supports direct bit set/reset capability for individual pin control without read-modify-write operations
• Features TTL compatibility and bus hold circuitry to eliminate the need for external pull-up resistors
• Delivers high-speed operation with no wait states when interfacing with 5MHz and 8MHz processors

Applications

• General-purpose programmable I/O expansion for microprocessor systems
• Interfacing with 80C86 and 80C88 microprocessors
• Industrial control applications requiring parallel data acquisition

Procurement Notes

Verify RoHS compliance status carefully as listings indicate non-compliance. Confirm moisture sensitivity level (MSL 2) requirements for surface mount assembly processes. Check current availability as the part may be discontinued or subject to limited stock constraints from distributors.

Selection Notes

Select this component for designs requiring standard 8255A pin compatibility with lower power consumption than NMOS versions. Ensure the application environment stays within the 0°C to 70°C commercial temperature range. Verify that the 44-MQFP package dimensions fit the PCB layout constraints.

Part Context

The CQ82C55A belongs to the 82C55A series of CMOS Programmable Peripheral Interfaces. It serves as a high-performance, low-power alternative to the legacy NMOS 8255A. The device maintains functional equivalence while offering improved electrical characteristics and reduced standby power consumption through advanced silicon gate CMOS processing.

Replacement Considerations

CS82C55A-5Z offers industrial temperature range (-40°C to +85°C) and PLCC-44 packaging. ID82C55A provides CDIP-40 through-hole mounting option with ESD protection. IQ82C55AZ96 is an MQFP variant but is listed as end-of-life.