Infineon Technologies CY7C136-25JXC

Overview

CY7C136-25JXC from Cypress Semiconductor is a 2K × 8 true dual-port static RAM with independent left/right ports, 25 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 master-mode arbitration for 16-bit+ bus expansion in multiprocessor systems.

For engineers reviewing the CY7C136-25JXC datasheet, CY7C136-25JXC pinout, CY7C136-25JXC application, or CY7C136-25JXC equivalent, key selection criteria include BUSY/INT flag timing (tBLA = 20 ns), asymmetric standby current (ISB2 = 75 mA), and open-drain BUSY output requiring external pull-up - critical for real-time arbitration in DSP cache and bit-slice architectures.

Technical Context

This device implements fully asynchronous dual-port architecture with separate CE, R/W, and OE controls per port, enabling concurrent read/write operations across independent address/data buses. The arbitration logic resolves contention via open-drain BUSY flags and priority-based interrupt signaling (INTL/INTR) on dedicated pins.

It operates in commercial (0°C to +70°C) and industrial (–40°C to +85°C) temperature ranges with automatic power-down controlled per port. CMOS process ensures low ICC (110 mA max) and ISB3 (15 µA) under CMOS input conditions, supporting low-power embedded buffering.

Key Specifications

Pinout & Package

Package: 52-pin Plastic Leaded Chip Carrier (PLCC), JEDEC MS-026AC, body size 19.1 mm × 19.1 mm, 0.050-inch lead pitch, surface-mount with gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C136-25WXC and CY7C136A-25JXC, the CY7C136-25JXC offers socket-compatible PLCC packaging for rapid validation, while retaining identical arbitration behavior and 25 ns timing - making it optimal for lab evaluation and legacy system upgrades where footprint interchangeability is mandatory.

Availability

CY7C136-25JXC is available at Aetrix Electronics and suitable for DSP cache buffers, multiprocessor shared memory, bit-slice CPU interfaces, and real-time video frame buffers requiring stable component supply across extended product lifecycles.

Supply support for CY7C136-25JXC 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 industrial, automotive, and communications systems.

The CY7C136 belongs to Cypress's legacy dual-port SRAM product line, engineered specifically for deterministic, low-latency shared memory in real-time embedded systems where bus arbitration and inter-processor signaling are critical.

FAQ

Is CY7C136-25JXC pin-compatible with CY7C136-25WXC?

Yes - both share identical 52-pin signal mapping and electrical specifications. The only difference is package type: JXC denotes PLCC, WXC denotes PQFP. Mechanical mounting differs, but PCB layout and firmware require no changes. Thermal and EMI performance vary due to package geometry, not pin function.

What external components are required for BUSY and INT pins?

BUSYL and BUSYR are open-drain outputs requiring 4.7 kΩ pull-up resistors to VCC (Pin 48). INTL and INTR also need pull-ups if used as interrupt sources for microcontrollers lacking internal weak pull-ups. No capacitors or termination networks are specified in the datasheet for these signals under standard 25 ns operation.

Can CY7C136-25JXC operate at 3.3 V?

No - the device is specified only for 5 V ±10% (4.5–5.5 V). Applying 3.3 V violates Absolute Maximum Ratings and results in undefined behavior, including failure to meet 25 ns access time, incorrect BUSY assertion, or data retention loss. A level-shifting interface is required for 3.3 V systems.

How does the automatic power-down feature work per port?

When CEL (Pin 1) or CER (Pin 46) is driven HIGH, the corresponding port enters low-power standby. ISB2 = 75 mA (one port active) drops to ISB1 = 35 mA (both ports disabled). Power-down is immediate with no latency; no command sequence or register write is needed - it is purely hardware-controlled by CE state.