Infineon Technologies CY7C0241-55AXI

Overview

CY7C0241-55AXI from Cypress Semiconductor is a 4K x 18 true dual-port static RAM with on-chip arbitration, semaphores, and INT/BUSY flags for interprocessor communication. It operates at 5 V ±10%, supports fully asynchronous read/write on independent left/right ports, delivers 55 ns maximum access time, and features automatic power-down per port via CE control. Used in multiprocessor status buffering and video memory coherency management.

For engineers reviewing the CY7C0241-55AXI datasheet, CY7C0241-55AXI pinout, CY7C0241-55AXI application, or CY7C0241-55AXI equivalent, key selection considerations include 4K × 18 organization, 55 ns access timing, M/S pin for master/slave expansion, semaphore latch behavior, and TQFP-100 Pb-free package compatibility.

Technical Context

The CY7C0241-55AXI implements true dual-port SRAM architecture with independent address/data/control buses per port (A0L–A11L/I/O0L–I/O17L and A0R–A11R/I/O0R–I/O17R), enabling simultaneous non-contenting reads of identical memory locations. Its on-chip arbitration logic resolves contention using BUSY flag assertion with tBLA/tBLC timing, while semaphore latches (8 total) provide software-controlled resource locking via SEM-enabled access to dedicated latch space.

Interrupt signaling uses upper two memory addresses (FFEh/FFFh) as mailboxes: write to opposite port's mailbox triggers INTx assertion; reading the mailbox resets the flag. The M/S pin configures BUSY as output (master) or input (slave), enabling 36-bit-wide memory expansion without external logic-critical for synchronized dual-CPU I/O buffering in industrial controllers.

Key Specifications

Pinout & Package

CY7C0241-55AXI is housed in a 100-pin Thin Quad Plastic Flatpack (TQFP) with exposed pad, RoHS-compliant Pb-free finish. Pin layout supports symmetrical left/right port mirroring and dedicated control signals for semaphore, interrupt, and master/slave configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT70V25L25PF and IS61LV25616AL-10TL, CY7C0241-55AXI uniquely integrates 4K × 18 dual-port memory, hardware semaphores, and M/S expandability in a single 5 V, industrial-temp TQFP package-enabling direct replacement of multi-chip arbitration solutions in space-constrained embedded designs.

Availability

CY7C0241-55AXI is available at Aetrix Electronics and suitable for industrial PLC I/O buffering, dual-core video frame synchronization, and telecom line card status exchange requiring stable component supply across extended product lifecycles.

Supply support for CY7C0241-55AXI 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.

The CY7C0241 belongs to Cypress's legacy dual-port SRAM product line, engineered specifically for deterministic interprocessor communication in real-time embedded systems with strict timing and coherency requirements.

FAQ

What is the function of the M/S pin on CY7C0241-55AXI?

The M/S pin configures the device as master (M/S = HIGH) or slave (M/S = LOW). In master mode, BUSY pins drive outputs to signal arbitration results; in slave mode, BUSY pins accept inputs from a master device. This enables seamless 36-bit memory expansion using multiple CY7C0241 chips without external logic.

How do semaphores operate in CY7C0241-55AXI?

Semaphores are eight dedicated latches accessed via SEM pin assertion (with CE high). Writing '0' to a semaphore grants exclusive access to that resource; writing '1' releases it. Both ports read the same latch value, but only the side that wrote '0' may modify it-ensuring atomic resource allocation without software locks.

Can CY7C0241-55AXI perform simultaneous reads and writes to the same address?

No-simultaneous write-to-read access to the same address causes non-deterministic output due to internal flowthrough delay. The BUSY flag asserts to indicate contention, and arbitration determines which port gains access. Simultaneous reads to the same location are fully supported and return identical valid data on both ports.

What is the role of the INTL and INTR pins?

INTL and INTR are open-drain interrupt outputs tied to mailbox addresses FFEh (left port mailbox) and FFFh (right port mailbox). A write to the opposite port's mailbox asserts the corresponding INT pin; reading that mailbox clears the flag. This provides hardware-synchronized, zero-latency interprocessor messaging without polling overhead.