Infineon Technologies CY7C131-55NXCT

Overview

CY7C131-55NXCT 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 PQFP package. It enables simultaneous reads of the same memory location and supports port-to-port interrupt and arbitration logic for multi-processor cache and DSP buffer applications.

For engineers reviewing the CY7C131-55NXCT datasheet, CY7C131-55NXCT pinout, CY7C131-55NXCT application, or CY7C131-55NXCT equivalent, key selection criteria include BUSY/INT flag timing, asymmetric standby current (ISB1 = 35 mA), CMOS-compatible I/O levels, and master-only dual-port configuration in 52-pin PQFP.

Technical Context

This device implements fully asynchronous dual-port SRAM architecture with separate CE/R/W/OE controls per port and hardware arbitration logic to resolve contention on shared addresses. The BUSY output (open-drain, requires pull-up) signals concurrent access attempts, while INT flags data writes to dedicated locations (3FFH left, 3FEH right).

It supports automatic power-down per port via CE assertion and delivers guaranteed 55 ns read/write cycle times under commercial temperature range (0°C to +70°C) at 5 V ±10%. Standby current drops to 35 mA (both ports disabled, TTL inputs) or 15 mA (CMOS input conditions).

Key Specifications

Pinout & Package

Package: 52-pin Plastic Quad Flat Pack (PQFP), RoHS-compliant, body size 10 mm × 10 mm, 0.65 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C131-55AXCT, this part trades industrial temperature rating for lower cost and tighter commercial-spec timing margins; compared with CY7C141-55NXCT, it provides autonomous arbitration and interrupt generation-making it self-contained for standalone dual-processor interfacing.

Availability

CY7C131-55NXCT is available at Aetrix Electronics and suitable for DSP cache memory, bit-slice processor buffers, and multi-processor communication systems requiring stable component supply and long-term obsolescence management.

Supply support for CY7C131-55NXCT 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) is a fabless semiconductor company specializing in memory, microcontrollers, and programmable solutions for embedded systems.

The CY7C13x series was designed specifically for high-reliability, low-latency shared-memory applications in digital signal processing, real-time control, and multi-processor architectures where deterministic access timing and hardware arbitration are mandatory.

FAQ

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

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 and serves as a hardware handshake signal to stall the contending port until the conflict resolves, ensuring data integrity without software intervention.

Can CY7C131-55NXCT operate with mixed voltage interfaces?

No. CY7C131-55NXCT is strictly a 5 V ±10% device with VIH = 2.2 V min and VIL = 0.8 V max. It does not support 3.3 V or 2.5 V I/O interfaces natively; level translation circuitry is required for connection to lower-voltage logic families.

How does the INT flag work in inter-processor communication?

The INT flag asserts when data is written to dedicated addresses: 3FFH (left port) or 3FEH (right port). Each port's INT pin is independent and remains asserted until the corresponding port performs a read from that address, enabling reliable, edge-triggered notification of new data without polling overhead.

Is CY7C131-55NXCT pin-compatible with CY7C130-55NXCT?

No. CY7C131-55NXCT uses a 52-pin PQFP package, while CY7C130-55NXCT is packaged in a 48-pin DIP. Although functionally identical, their physical pinouts, dimensions, and thermal profiles differ significantly-requiring separate PCB footprints and layout validation.