Infineon Technologies CY7C025-25AXCT

Overview

CY7C025-25AXCT from Cypress Semiconductor is an 8K × 16-bit true dual-port static RAM with on-chip arbitration, semaphores, and INT/BUSY flags. It supports fully asynchronous, independent read/write access on left and right ports, delivers 25 ns access time, consumes 150 mA typical active current, and operates at 5 V ±10% across commercial temperature range (0°C to +70°C). It is used in interprocessor communication buffers and dual-port video memory subsystems.

For engineers reviewing the CY7C025-25AXCT datasheet, CY7C025-25AXCT pinout, CY7C025-25AXCT application, or CY7C025-25AXCT equivalent, key selection considerations include dual-port arbitration timing (tPS = 10 ns), semaphore latch behavior, M/S-configurable master/slave expansion, and TQFP-100 package compatibility with 16-bit data bus systems.

Technical Context

The CY7C025-25AXCT implements a dedicated dual-port SRAM architecture with physically separate address/data/control paths per port, enabling concurrent access without external logic. Its on-chip arbitration resolves contention via BUSY assertion within tBLA = 8 ns (address match) or tBLC = 10 ns (CE low), and supports deterministic port prioritization only when tPS ≥ 10 ns is met.

Semaphore operation uses eight independent latches accessed via SEM pin with A0–A2 addressing; write-to-semaphore requires CE high and SEM low, and output latching prevents race conditions during cross-port reads. The INT flag leverages upper two memory locations (1FFEh/1FFFh) for mailbox-style inter-port messaging, resettable only by owner-read.

Key Specifications

Pinout & Package

Package: 100-pin Thin Quad Plastic Flatpack (TQFP), Pb-free, body size 14 mm × 14 mm, 0.5 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT70V25S-25PF and CY7C025-25AC, the CY7C025-25AXCT uniquely supports 5 V operation with native TQFP-100 thermal performance and integrated M/S expansion - making it optimal for cost-sensitive, mixed-signal industrial designs requiring no voltage translation or board re-spin.

Availability

CY7C025-25AXCT is available at Aetrix Electronics and suitable for interprocessor communication buffers, dual-port video frame buffers, and industrial PLC data exchange memory requiring stable component supply and long-term lifecycle support.

Supply support for CY7C025-25AXCT 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 logic solutions for industrial, automotive, and communications infrastructure.

The CY7C025 belongs to Cypress's dual-port SRAM product line, engineered specifically for deterministic, low-latency inter-processor data exchange in real-time embedded systems with strict timing and coherency requirements.

FAQ

What is the function of the M/S pin on CY7C025-25AXCT?

The M/S pin configures the device as master (M/S = HIGH) or slave (M/S = LOW) for word-width expansion. In master mode, BUSY pins output arbitration status; in slave mode, BUSY pins accept arbitration signals from a master device. This enables seamless 32-bit memory construction using two CY7C025s without external logic or timing adjustments.

How does semaphore arbitration work between left and right ports?

Semaphore latches (eight total) are accessed via SEM pin with A0–A2 addressing. Writing '0' to a semaphore grants exclusive ownership to that port; the opposite port reads '1' until ownership is released by writing '1'. Cross-port reads are latched to prevent race conditions, and simultaneous semaphore requests resolve within tSPS = 5 ns - guaranteeing one port wins.

Can CY7C025-25AXCT operate with 3.3 V I/O interfaces?

No. CY7C025-25AXCT requires 5 V ±10% supply (4.5–5.5 V) and is specified only for TTL/CMOS 5 V logic levels. Its inputs are not 3.3 V tolerant, and outputs swing rail-to-rail at 5 V. Interfacing with 3.3 V controllers requires level-shifting circuitry - unlike 3.3 V-compatible alternatives such as IDT70V25S.

What happens when both ports attempt to access the same memory location simultaneously?

On-chip arbitration asserts BUSY on the losing port within tBLA = 8 ns (address match) or tBLC = 10 ns (CE low). If tPS < 10 ns, resolution is non-deterministic. The winning port proceeds with access; the losing port must wait until BUSY deasserts before retrying. No data corruption occurs - only controlled delay is introduced.