Infineon Technologies CY7C131-55JXIT

Overview

CY7C131-55JXIT from Cypress Semiconductor is a 1 K × 8 true dual-port static RAM with independent left/right ports, 55 ns maximum access time, 5 V ±10% supply, and 52-pin PLCC package. It enables simultaneous read access to the same memory location and supports port-to-port communication via BUSY and INT flags in DSP cache, bit-slice, and multi-processor shared-memory systems.

For engineers reviewing the CY7C131-55JXIT datasheet, CY7C131-55JXIT pinout, CY7C131-55JXIT application, or CY7C131-55JXIT equivalent, key selection criteria include asynchronous dual-port timing, 55 ns access latency, BUSY arbitration logic, INT interrupt flag behavior, and compatibility with CY7C141 slave devices for 16-bit expansion.

Technical Context

The device implements fully asynchronous dual-port architecture with separate CE, R/W, and OE controls per port, enabling independent read/write operations without clock synchronization. Arbitration logic resolves contention when both ports access the same address, asserting open-drain BUSY outputs requiring external pull-up resistors.

INT flags operate at fixed locations (3FF_L, 3FE_R) to signal inter-port data placement, and automatic power-down is triggered independently per port via CE deassertion. The 0.65 µm CMOS process ensures stable operation across commercial (0°C to +70°C) and industrial (–40°C to +85°C) temperature ranges.

Key Specifications

Pinout & Package

Package: 52-pin Plastic Leaded Chip Carrier (PLCC), JEDEC standard MO-047AC, lead-free (Pb-free) compliant, body size 19.1 mm × 19.1 mm, 0.5 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C131-45JXIT, this part trades 10 ns speed for lower power consumption and wider voltage tolerance margin; versus CY7C141-55JXIT, it provides full master functionality including arbitration and interrupt generation essential for autonomous dual-port operation.

Availability

CY7C131-55JXIT is available at Aetrix Electronics and suitable for DSP cache memory, bit-slice processor interfacing, and multi-processor shared memory systems requiring stable component supply across extended temperature ranges.

Supply support for CY7C131-55JXIT 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-performance memory and programmable solutions for embedded systems, emphasizing reliability, low power, and interoperability.

This device belongs to Cypress's legacy dual-port SRAM product line, engineered specifically for deterministic, low-latency shared memory in real-time signal processing and control architectures.

FAQ

What is the function of the BUSY pin on CY7C131-55JXIT?

The BUSY pin is an open-drain output that asserts LOW when its port attempts to access a memory location currently being accessed by the opposite port. It requires an external pull-up resistor (typically 4.7 kΩ to V_CC) and serves as hardware arbitration feedback to prevent data corruption during contention. It does not auto-retry or stall-software must monitor and reissue the access.

Can CY7C131-55JXIT operate with a 3.3 V supply?

No. CY7C131-55JXIT is specified only for 5 V ±10% (4.5–5.5 V) operation. Its input thresholds (VIH = 2.2 V, VIL = 0.8 V) and output drive strength are designed for TTL/5 V CMOS compatibility. Applying 3.3 V violates absolute maximum ratings and will cause functional failure or accelerated wear-out.

How does the INT flag work in port-to-port communication?

INTL asserts when data is written to address 3FF_H (1023) on the left port; INTR asserts when data is written to 3FE_H (1022) on the right port. Both are open-drain outputs requiring pull-up resistors. They provide hardware-triggered event signaling-no polling needed-and reset automatically upon read access to their respective flag addresses.

Is CY7C131-55JXIT pin-compatible with CY7C130-55JXI?

No. CY7C131-55JXIT uses a 52-pin PLCC package, while CY7C130-55JXI uses a 48-pin DIP. Though functionally identical, their pin counts and layouts differ: CY7C131 adds NC pins and rearranges I/O positioning to accommodate the PLCC form factor. PCB layout and socketing are not interchangeable.