Infineon Technologies CY7C024-55AC

Overview

CY7C024-55AC from Cypress Semiconductor is a 4K × 16-bit true dual-port static RAM with independent left/right ports, on-chip arbitration logic, semaphores, and INT/BUSY flags - designed for interprocessor communication and real-time shared-memory buffering in embedded control systems. It operates at 5 V ±10%, supports 55 ns access time, delivers 150 mA typical active current, and features automatic power-down per port via CE control.

For engineers reviewing the CY7C024-55AC datasheet, CY7C024-55AC pinout, CY7C024-55AC application, or CY7C024-55AC equivalent, key selection criteria include dual-port contention resolution timing (tPS = 5 ns), semaphore latch behavior, M/S pin configuration for master/slave expansion, and compatibility with 84-pin PLCC footprint in industrial temperature range (–40°C to +85°C).

Technical Context

This device implements fully asynchronous dual-port SRAM architecture with separate address, data, and control buses per port (A0L–A11L / A0R–A11R, I/O0L–I/O15L / I/O0R–I/O15R), enabling concurrent read/write operations to any memory location. On-chip arbitration resolves port conflicts using BUSY flag assertion with tBLA = 5 ns latency and tPS = 5 ns setup window.

Semaphore logic comprises eight dedicated latches accessible via SEM pin activation (A0–A2 as semaphore address), supporting token-based resource sharing without external logic. The M/S pin configures BUSY as output (master) or input (slave), enabling 32-bit-wide memory expansion using multiple devices without discrete glue logic.

Key Specifications

Pinout & Package

Available in 84-pin Plastic Leaded Chip Carrier (PLCC) package with 0.050" lead pitch, JEDEC MS-026 compliant, Pb-free option available. Pin layout supports through-hole mounting and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-port SRAM applications.

Compared with IDT70V25L25PF and CY7C028-55AC, the CY7C024-55AC uniquely balances 5 V operation, hardware semaphore support, and M/S expandability in an 84-pin PLCC - making it optimal for cost-sensitive industrial controllers where voltage compatibility and resource coordination are non-negotiable.

Availability

CY7C024-55AC is available at Aetrix Electronics and suitable for industrial PLCs, real-time motion controllers, dual-port video subsystems, and communications gateways requiring stable component supply across extended product lifecycles.

Supply support for CY7C024-55AC 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

Cypress Semiconductor (now part of Infineon Technologies) designs high-reliability memory and programmable solutions for industrial, automotive, and embedded markets, with emphasis on integration and system-level robustness.

The CY7C024 series belongs to Cypress's legacy dual-port SRAM product line, engineered specifically for deterministic interprocessor communication in safety-critical and real-time control applications where hardware arbitration and semaphore coherency are mandatory.

FAQ

What is the function of the M/S pin in CY7C024-55AC?

The M/S pin configures the device as master (M/S = HIGH) or slave (M/S = LOW). In master mode, BUSY pins act as outputs signaling arbitration results to downstream slaves; in slave mode, BUSY pins accept arbitration signals from a master. This enables seamless 32-bit memory expansion without external logic or timing constraints beyond tBLC (5 ns).

How do the semaphore latches operate and what address space do they occupy?

Semaphores are eight dedicated latches accessed only when SEM is asserted LOW (with CE HIGH). A0–A2 select the latch (0–7); I/O0 carries the token value (0 = acquired, 1 = free). Semaphores reside outside main memory - no address lines beyond A2 affect them, and reads return the same value on all I/O lines. Acquire/release is atomic and collision-resistant per tSPS timing.

Can CY7C024-55AC operate reliably at 55 ns access time over the full industrial temperature range?

Yes - the "-55AC" suffix denotes guaranteed 55 ns maximum access time (tACE) across –40°C to +85°C at VCC = 5 V ±10%. This is validated per Cypress datasheet Rev. *D, Table 5, with derating applied for voltage and temperature extremes. No external wait-state logic is needed for compliant microcontrollers.

What happens if both ports attempt to write to the same memory location simultaneously?

On-chip arbitration asserts BUSY on the losing port within tBLA = 5 ns of address match. The winning port completes its write; the losing port's write is blocked until BUSY deasserts. If tPS < 5 ns is violated, arbitration outcome becomes unpredictable. Data integrity is preserved - no corruption occurs, but timing determinism requires adherence to tPS specification.