Infineon Technologies CY7C025-25AXI

Overview

CY7C025-25AXI from Cypress Semiconductor is an 8K × 16-bit true dual-port static RAM with on-chip arbitration, semaphores, and INT/BUSY flags. It enables simultaneous asynchronous read/write access to shared memory by two independent processors or data paths, supports master/slave expansion to 32-bit bus width, and operates at 25 ns access time with 5 V ±10% supply across industrial temperature range (–40°C to +85°C). Used in interprocessor communication buffers and dual-port video frame stores.

For engineers reviewing the CY7C025-25AXI datasheet, CY7C025-25AXI pinout, CY7C025-25AXI application, or CY7C025-25AXI equivalent, key selection criteria include dual-port arbitration timing (tPS = 15 ns), semaphore latch count (8), BUSY/INT flag behavior in master/slave mode, and compatibility with 84-pin PLCC or 100-pin TQFP PCB footprints.

Technical Context

The CY7C025-25AXI implements fully asynchronous dual-port architecture with independent CE/R/W/OE control per port, enabling concurrent access without external synchronization. Its on-chip arbitration resolves address-contention events via deterministic BUSY assertion (tBLA = 10 ns, tBLC = 12 ns) and guarantees exclusive access when tPS ≤ 15 ns is met.

It integrates eight dedicated semaphore latches accessible via SEM pin, supporting software-controlled resource locking between ports. The M/S pin configures BUSY as output (master) or input (slave), enabling seamless 32-bit memory expansion without discrete logic - critical for multiprocessor interconnects requiring deterministic handshaking.

Key Specifications

Pinout & Package

Available in 84-pin PLCC (lead-free) and 100-pin TQFP (lead-free); CY7C025-25AXI is specified for the 84-pin PLCC variant per ordering code suffix "X" (PLCC) and "I" (industrial temp).

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, CY7C025-25AXI uniquely supports industrial temperature operation in both PLCC and TQFP packages while retaining 5 V native interface - critical for legacy industrial control upgrades without voltage rail redesign.

Availability

CY7C025-25AXI is available at Aetrix Electronics and suitable for interprocessor communication buffers, dual-port video frame stores, multiprocessor status sharing, and communications protocol stack buffers requiring stable component supply across extended lifecycle programs.

Supply support for CY7C025-25AXI 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 communications infrastructure.

CY7C025 belongs to the CY7C02x dual-port SRAM product line, engineered specifically for deterministic, low-latency interprocessor data exchange in real-time embedded systems without external arbitration logic.

FAQ

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

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 outcome to slaves; in slave mode, BUSY pins become inputs receiving arbitration status from the master. This enables daisy-chained 32-bit memory expansion using identical CY7C025-25AXI units without external logic.

How do the INTL and INTR pins operate in mailbox mode?

INTL and INTR are open-drain interrupt flags triggered when the opposite port writes to dedicated mailbox addresses (1FFE for left port, 1FFF for right port). The interrupt remains asserted until the owning port reads its mailbox - providing edge-triggered, self-acknowledging inter-port signaling without polling overhead or external interrupt controllers.

Can CY7C025-25AXI perform simultaneous read and write to the same memory location?

No - simultaneous access to the same address triggers on-chip arbitration. One port gains access while the other receives BUSY assertion. However, simultaneous reads to the same location are fully supported and return valid data on both ports without contention or delay, leveraging true dual-port cell architecture.

What is the role of the SEM pin during semaphore operations?

The SEM pin acts as a dedicated chip select for the 8 semaphore latches, overriding CE. When SEM is LOW, A0–A2 select the semaphore address, and I/O0 carries the token value (0 = acquire, 1 = release). OE and R/W retain standard memory timing roles, enabling atomic semaphore access with hardware-enforced exclusivity.