Infineon Technologies CY7C1399BN-15ZXIT

Overview

CY7C1399BN-15ZXIT from Cypress Semiconductor is a 256K (32K × 8) high-speed CMOS static RAM operating at 3.3 V, featuring 15 ns access time, industrial temperature range (–40°C to +85°C), and automatic CE-controlled power-down reducing standby current to 500 µA. It uses low-power alpha-immune 6T cells and is packaged in a Pb-free 28-pin TSOP I (8 × 13.4 mm) for space-constrained embedded memory expansion.

For engineers reviewing the CY7C1399BN-15ZXIT datasheet, CY7C1399BN-15ZXIT pinout, CY7C1399BN-15ZXIT application, or CY7C1399BN-15ZXIT equivalent, key selection criteria include its TTL/CMOS-compatible control interface (CE/OE/WE), tristate I/O drivers, 32K-word addressability with A0–A14, and dual-mode power management supporting low-voltage cache and buffer designs.

Technical Context

The CY7C1399BN-15ZXIT implements asynchronous SRAM architecture with independent chip enable (active LOW CE), output enable (active LOW OE), and write enable (active LOW WE) for precise read/write control. Its 32K × 8 organization maps directly to 15-bit address bus (A0–A14) and 8-bit bidirectional data bus (I/O0–I/O7), enabling seamless integration into microcontroller and FPGA memory subsystems without address decoding overhead.

It features automatic power-down when CE is HIGH, reducing ICC to ≤500 µA under CMOS input conditions, and supports three distinct operating modes: read (CE=LOW, OE=LOW, WE=HIGH), write (CE=LOW, WE=LOW), and high-impedance standby (CE=HIGH). Timing is guaranteed across industrial temperature with tRC = 15 ns, tAA = 15 ns, and tDOE = 6 ns.

Key Specifications

Pinout & Package

Package: 28-pin TSOP I (8 × 13.4 mm), Pb-free, JEDEC MO-153 compliant, 300-mil body width.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IS61LV25616AL-15TQLI and AS6C4008-15ZIN, the CY7C1399BN-15ZXIT offers optimal fit for 8-bit bus-constrained industrial controllers, delivering verified 500 µA standby at –40°C/+85°C while maintaining identical 28-pin TSOP I mechanical compatibility and lower active power than the AS6C4008 variant.

Availability

CY7C1399BN-15ZXIT is available at Aetrix Electronics and suitable for industrial PLC memory buffers, automotive body control modules, medical diagnostic imaging FIFOs, and avionics data acquisition buffers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY7C1399BN-15ZXIT 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 high-reliability memory, PSoC, and USB/USB-C solutions for industrial and automotive markets.

The CY7C1399BN belongs to Cypress's Fast Asynchronous SRAM family, designed specifically for low-latency, low-voltage memory expansion in resource-constrained embedded systems where deterministic timing and industrial-grade reliability are mandatory.

FAQ

Is CY7C1399BN-15ZXIT pin-compatible with CY7C1399BN-12ZXI?

Yes - both use identical 28-pin TSOP I (51-85071) packaging and share identical pin functions (A0–A14, I/O0–I/O7, CE, OE, WE, VCC, GND). The only difference is access time: 12 ns vs. 15 ns. Timing-critical systems must verify tRC, tAA, and tDOE margins against their clock domain.

Does CY7C1399BN-15ZXIT support battery backup operation?

Yes - it retains data at VCC = 2.0 V (VDR) with ICCDR ≤20 µA, enabling direct connection to coin-cell batteries during main power loss. The device enters data retention mode automatically when CE is deasserted and VCC drops to 2.0 V, requiring no external control signals.

What is the maximum capacitive load supported on I/O pins?

The datasheet specifies CL = 30 pF for AC timing measurements (tDOE, tHZOE, etc.), and output capacitance (COUT) is rated at 6 pF. Driving loads >30 pF may violate tHZOE (6 ns) and tLZOE (0 ns) specifications, potentially causing bus contention or read corruption in multi-drop configurations.

Can CY7C1399BN-15ZXIT be used with 5 V tolerant microcontrollers?

No - all inputs (A0–A14, CE, OE, WE) have absolute maximum VIH = VCC + 0.3 V = 3.6 V. Direct connection to 5 V logic violates the DC input voltage rating (–0.5 V to VCC + 0.3 V) and risks permanent damage. Level-shifting circuitry is required for 5 V host interfaces.