Infineon Technologies CY7C144-15JXCT

Overview

CY7C144-15JXCT from Cypress Semiconductor is an 8K × 8 true dual-port static RAM with independent left/right ports, 15 ns access time, TTL-compatible I/O, and integrated semaphore, interrupt, and busy arbitration logic. It enables simultaneous asynchronous read/write access to the same memory location and is used in interprocessor communication buffers and dual-port video frame stores.

For engineers reviewing the CY7C144-15JXCT datasheet, CY7C144-15JXCT pinout, CY7C144-15JXCT application, or CY7C144-15JXCT equivalent, key selection criteria include dual-port arbitration behavior, semaphore latch timing (tSOP, tSWRD), INT/ BUSY flag push-pull drive capability, and master/slave expansion support via M/S pin.

Technical Context

The CY7C144-15JXCT implements fully asynchronous dual-port SRAM architecture with separate CE, OE, R/W, and SEM controls per port. Its on-chip arbitration resolves contention via BUSY assertion within tBLA/tBLC, and supports deterministic port-to-port flowthrough delay (tDDD) for cross-port data visibility.

Semaphore operation uses A0–A2 as address lines with SEM as enable; only I/O0L/R participates in semaphore writes. INT flags are set/cleared by writes to fixed addresses (1FFE/1FFF) and operate as push-pull outputs without external pull-ups.

Key Specifications

Pinout & Package

Package: 68-pin PLCC (plastic leaded chip carrier), body size 24.2 mm × 24.2 mm, JEDEC MS-026AC compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT70V25L15PF and IS61LV5128-15K, the CY7C144-15JXCT uniquely integrates arbitration, semaphore, and interrupt logic in a 5 V, 15 ns dual-port SRAM-enabling direct CPU-to-CPU communication without external components or voltage translation.

Availability

CY7C144-15JXCT is available at Aetrix Electronics and suitable for interprocessor communication buffers, dual-port video frame stores, communications protocol stack buffers, and industrial PLC dual-task memory requiring stable component supply and long-lifecycle availability.

Supply support for CY7C144-15JXCT 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 CY7C144 product line delivers integrated dual-port SRAMs with on-chip arbitration and synchronization logic specifically for deterministic multi-processor memory sharing in real-time embedded systems.

FAQ

What is the function of the M/S pin on CY7C144-15JXCT?

The M/S (Master/Slave Select) pin configures the device for bus-width expansion: when HIGH, it operates as a master with BUSY pins as push-pull outputs; when LOW, it operates as a slave with BUSY pins as inputs. This allows cascading multiple CY7C144 devices to build 16-bit or wider dual-port memory without external logic.

How do the semaphore latches operate, and what timing constraints apply?

Semaphores are eight dedicated latches accessed via SEML/SEMR with A0–A2 as address lines. Writing a 0 to I/O0L/R asserts the latch; reading returns its state. After a semaphore write, SEM or OE must be deasserted for tSOP (min. 10 ns) before reading. The semaphore value appears tSWRD + tDOE after the write rising edge.

Can INTL and INTR be used without external pull-up resistors?

Yes. Both INTL and INTR are push-pull outputs per the datasheet (page 4, Note 2), meaning they actively drive HIGH and LOW states. No external pull-up resistors are required, simplifying PCB layout and ensuring reliable flag assertion timing in noise-sensitive environments.

What happens during simultaneous access to the same memory location by both ports?

When both ports attempt access within tPS (10 ns), on-chip arbitration asserts BUSYL/BUSYR to indicate contention. One port gains guaranteed access; the other sees BUSY asserted and must retry. If tPS is violated, access is still granted to one port-but which port succeeds is indeterminate per datasheet page 4.