Infineon Technologies CY7C144-15AXIT

Overview

CY7C144-15AXIT from Cypress Semiconductor is an 8K × 8 true dual-port static RAM with independent asynchronous access on left and right ports, 15 ns access time, TTL-compatible I/O, and integrated semaphore/INT/BUSY arbitration logic. It enables interprocessor communication in real-time embedded systems requiring deterministic memory sharing, such as dual-CPU industrial controllers.

For engineers reviewing the CY7C144-15AXIT datasheet, CY7C144-15AXIT pinout, CY7C144-15AXIT application, or CY7C144-15AXIT equivalent, key selection criteria include dual-port contention resolution timing (tPS = 15 ns), semaphore latch behavior (8 shared latches, A0–A2 address mapping), INT flag mailbox addressing (1FFE/1FFF), and M/S-configurable master/slave bus expansion.

Technical Context

The CY7C144-15AXIT implements hardware-based arbitration using dedicated BUSY outputs (push-pull, no pull-up required) that assert within tBLA = 10 ns of address match to resolve simultaneous access to identical memory locations. Its semaphore subsystem operates independently of main memory via SEML/SEMR enable, using only A0–A2 for latch selection and I/O0 for write data.

Each port features fully independent control: CE, R/W, OE, and interrupt generation triggered by writes to fixed addresses (1FFE for INTL, 1FFF for INTR). The M/S pin configures BUSYL/BUSYR as outputs (master) or inputs (slave), enabling seamless 16-bit+ width expansion without external logic.

Key Specifications

Pinout & Package

Package: 68-pin PLCC (plastic leaded chip carrier), RoHS-compliant, surface-mountable with gull-wing leads and internal heat slug.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT70V25L15PF and IS61LV5128AL-15KLI, the CY7C144-15AXIT uniquely delivers 5 V TTL compatibility, integrated BUSY/INT/SEM logic, and true simultaneous access - essential for legacy industrial and avionics platforms where voltage and timing constraints preclude redesign.

Availability

CY7C144-15AXIT is available at Aetrix Electronics and suitable for industrial dual-CPU controllers, real-time video frame buffers, and communications protocol stack buffers requiring stable component supply across extended temperature ranges (–40°C to +85°C).

Supply support for CY7C144-15AXIT 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 aerospace applications.

The CY7C144 series targets deterministic interprocessor communication, providing hardware arbitration and synchronization primitives for systems where software-only coordination introduces unacceptable latency or jitter.

FAQ

What is the function of the M/S pin in CY7C144-15AXIT?

The M/S (Master/Slave Select) pin configures the device's BUSY signal behavior: when HIGH, BUSYL and BUSYR operate as push-pull outputs for master-mode arbitration; when LOW, they become inputs for slave-mode operation. This enables direct daisy-chaining of multiple CY7C144 devices to build wider memory words (e.g., 16-bit) without external logic or timing compensation.

How do the semaphore latches operate, and what address lines control them?

Semaphore access is enabled by asserting SEML or SEMR LOW while keeping the corresponding CE HIGH. Only address lines A0–A2 select among the eight latches; other address bits are ignored. Writing a 0 to I/O0L or I/O0R requests ownership; reading returns the current latch state. Initialization requires writing 1 to all semaphores from both ports at power-up to ensure clean release state.

Can INTL and INTR be used simultaneously for bidirectional messaging?

Yes - INTL is set when the right port writes to address 1FFE and cleared when the left port reads it; INTR is set when the left port writes to 1FFF and cleared when the right port reads it. This creates two independent mailbox channels, allowing full-duplex status exchange without shared memory address conflicts or software arbitration.

What is the maximum operating current specification, and under what conditions is it measured?

The maximum operating current is 220 mA (commercial grade), measured with VCC = 5.5 V, all outputs loaded at –4 mA (VOH), f = fMAX = 1/tRC, and both ports actively accessing memory. This value reflects worst-case dynamic power consumption during sustained dual-port read/write cycles and informs thermal design and regulator sizing.