Infineon Technologies CY7C144E-55JXCT

Overview

CY7C144E-55JXCT from Cypress Semiconductor is an 8K × 8 true dual-port static RAM with integrated semaphore, interrupt, and busy arbitration logic. It enables simultaneous asynchronous read access to the same memory location by independent left/right ports, supports master/slave expansion for 16-bit+ bus width, and delivers 55 ns access time with 180 mA typical active current and 0.05 mA CMOS standby current. Used in interprocessor communication buffers and dual-port video frame stores.

For engineers reviewing the CY7C144E-55JXCT datasheet, CY7C144E-55JXCT pinout, CY7C144E-55JXCT application, or CY7C144E-55JXCT equivalent, key selection criteria include dual-port arbitration timing (tPS, tBLA), semaphore latch behavior, M/S mode configuration, INT/BUSY flag drive type (push-pull), and PLCC-68 vs TQFP-64 package compatibility.

Technical Context

The CY7C144E-55JXCT implements fully asynchronous dual-port operation with independent CE/R/W/OE control per port, on-chip busy arbitration resolving contention within tPS (5 ns max), and push-pull INT/BUSY outputs requiring no external pull-ups. Its semaphore logic uses eight shared latches addressed via A0–A2 under SEM enable, with write-to-semaphore using only I/O0L/I/O0R.

Master/slave mode is selected by the M/S pin: HIGH configures BUSYL/BUSYR as outputs for cascading, LOW makes them inputs for slave operation. Automatic power-down is triggered per port by CE deassertion or SEM assertion, with ISB3 = 0.05 mA (CMOS-level standby) confirmed at VCC = 5 V and TA = 25 °C.

Key Specifications

Pinout & Package

Package: 68-pin Plastic Leaded Chip Carrier (PLCC), JEDEC MS-026AC compliant, lead-free (Pb-free) variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT70V25L25PF and CY7C144AV-55JXC, the CY7C144E-55JXCT uniquely combines 5 V TTL compatibility, Pb-free PLCC-68 packaging, M/S-enabled bus expansion, and guaranteed 0.05 mA ISB3 standby - making it optimal for industrial control upgrades requiring drop-in reliability and regulatory compliance.

Availability

CY7C144E-55JXCT is available at Aetrix Electronics and suitable for interprocessor communication buffers, dual-port video frame stores, and industrial motion control data exchange requiring stable component supply across multi-year production cycles.

Supply support for CY7C144E-55JXCT 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 CY7C144E belongs to Cypress's dual-port SRAM product line, engineered specifically for deterministic, low-latency interprocessor data exchange in real-time embedded systems where hardware arbitration and semaphore coherency are mandatory.

FAQ

What is the function of the M/S pin in CY7C144E-55JXCT?

The M/S (Master/Slave) pin configures the device for bus-width expansion: when HIGH, BUSYL and BUSYR operate as push-pull outputs to signal arbitration results to downstream slaves; when LOW, they become inputs to accept BUSY signals from a master. This eliminates external logic for building 16-bit or wider dual-port memory arrays.

How do the semaphore latches work, and what address range do they occupy?

The eight semaphore latches are accessed by asserting SEML or SEMR LOW while holding CE HIGH; A0–A2 select the latch (0–7), and only I/O0L or I/O0R carries the write value (0 = request, 1 = release). Semaphores reside outside main memory space - no address conflict with 0x0000–0x1FFF - and require explicit initialization to 1 at power-up.

Can INTL and INTR be used simultaneously for bidirectional messaging?

Yes: writing to left-port address 0x1FFE sets INTR (right-port interrupt), and writing to right-port address 0x1FFF sets INTL (left-port interrupt). Each flag clears only upon reading its respective address, enabling full-duplex mailbox operation without shared memory contention or polling overhead.

What is the minimum pulse width required for CE or R/W to ensure valid access?

The datasheet specifies tCE = 5 ns (minimum CE pulse width) and tW = 5 ns (minimum R/W pulse width) for reliable operation. Violating these violates the internal state machine timing, potentially causing invalid data capture or BUSY misassertion - verified under worst-case VCC = 4.5 V and TA = 70 °C conditions.