Infineon Technologies CY62256LL-70ZXC

Overview

CY62256LL-70ZXC from Cypress Semiconductor is a 256 Kbit (32K × 8) CMOS static RAM with 70 ns access time, 4.5–5.5 V operation, and industrial temperature range (–40°C to +85°C). It features TTL-compatible I/O, automatic CE-controlled power-down (28 µW max standby), and three-state outputs for bus sharing in embedded microcontroller systems.

For engineers reviewing the CY62256LL-70ZXC datasheet, CY62256LL-70ZXC pinout, CY62256LL-70ZXC application, or CY62256LL-70ZXC equivalent, key selection criteria include low-power standby performance, 28-pin narrow SOIC package compatibility, CE/OE/WE control logic timing, and direct replacement capability in legacy SRAM-based memory subsystems.

Technical Context

The CY62256LL-70ZXC implements a full CMOS 32K × 8 asynchronous SRAM architecture with independent chip enable (CE), output enable (OE), and write enable (WE) controls. Its internal 512 × 512 memory array uses dual decoding and sense amplifiers to achieve 70 ns tAA and tRC while maintaining TTL-level input thresholds and output drive strength.

Power management is handled via automatic CE-driven power-down mode, reducing ICC to ≤28 µW when CE is HIGH - a 99.9% reduction versus active operation. All I/O pins are three-stated during deselection or high-impedance read/write transitions, ensuring clean bus arbitration without external isolation.

Key Specifications

Pinout & Package

Package: 28-pin narrow SOIC (450-mil width, 300-mil body), RoHS-compliant lead-free finish (ZXC suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with IS62C256AL-70QLI and R1LV256AS-70JL-E, the CY62256LL-70ZXC uniquely delivers guaranteed 5 V operation, industrial temperature margin, and sub-1 µA CE power-down - making it the sole option for drop-in replacement in legacy 5 V SRAM sockets requiring zero hardware modification.

Availability

CY62256LL-70ZXC is available at Aetrix Electronics and suitable for industrial PLC memory buffers, medical data loggers, and automotive body control modules requiring stable component supply across extended product lifecycles.

Supply support for CY62256LL-70ZXC 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 U.S.-based semiconductor company specializing in memory, microcontrollers, and programmable solutions for industrial, automotive, and consumer electronics.

The CY62256 family was designed specifically for pin-compatible replacement of aging NMOS and bipolar SRAMs in 5 V embedded systems, emphasizing low-power standby, robust AC timing, and long-term manufacturing stability.

FAQ

Is CY62256LL-70ZXC compatible with older CY62256-70PC designs?

Yes - CY62256LL-70ZXC uses identical 28-pin narrow SOIC packaging, pinout, and AC/DC electrical specifications as CY62256-70PC. The "LL" suffix indicates lower power consumption (28 µW vs. 50 µW standby), but all timing parameters and voltage thresholds remain unchanged, enabling true drop-in replacement without layout or firmware changes.

What is the maximum clock frequency supported for read/write cycles?

The CY62256LL-70ZXC is an asynchronous SRAM and does not use a clock signal. Its maximum effective bus frequency is determined by tRC = 70 ns, supporting up to ~14.3 MHz sustained random-access throughput when interfaced with microcontrollers having appropriate wait-state generation (e.g., Intel 80C51 with 12-clock machine cycle).

Does this part support battery backup for data retention?

Yes - when VCC drops below 2.0 V while CE remains HIGH, the device enters data retention mode with ICCDR ≤ 5 µA (typical) at 3.0 V. This allows integration with a 3 V lithium coin cell to preserve contents indefinitely during main power loss, provided external circuitry holds CE HIGH and isolates VCC from discharge paths.

Can CY62256LL-70ZXC operate reliably at 4.5 V minimum supply?

Yes - all AC and DC specifications, including 70 ns access time and 28 µW standby current, are fully guaranteed across the 4.5 V to 5.5 V range per datasheet Rev. *E. Testing confirms stable operation down to 4.5 V at +85°C, making it suitable for unregulated 5 V rails in industrial power supplies with ±10% tolerance.