Infineon Technologies CY14E256Q5A-SXQ

Overview

CY14E256Q5A-SXQ from Cypress Semiconductor is a 256-Kbit (32K × 8) SPI nonvolatile SRAM with QuantumTrap technology, operating at 4.5–5.5 V and supporting 104 MHz fast-read SPI access. It performs automatic STORE on power-down using an external VCAP capacitor, supports hardware STORE via HSB pin, and delivers infinite SRAM write cycles with 20-year data retention at 85 °C. Used in industrial control loggers requiring deterministic power-loss data capture.

For engineers reviewing the CY14E256Q5A-SXQ datasheet, CY14E256Q5A-SXQ pinout, CY14E256Q5A-SXQ application, or CY14E256Q5A-SXQ equivalent, key selection criteria include VCC range compatibility (4.5–5.5 V), HSB-driven hardware STORE timing, VCAP-based AutoStore hold time, and SPI mode 0/3 support for legacy controller integration.

Technical Context

The device integrates SRAM and QuantumTrap nonvolatile cells per bit, enabling infinite read/write to volatile array while securing data via parallel STORE to SONOS-based nonvolatile elements. STORE operations erase-then-program the QuantumTrap layer, with status signaled via HSB pin and RDY bit in Status Register.

SPI interface operates as slave in modes 0 (CPOL=0, CPHA=0) and 3 (CPOL=1, CPHA=1), supporting standard READ/WRITE (≤40 MHz) and FAST_READ (≤104 MHz) with dummy byte. Special instructions (STORE, RECALL, ASDISB, ASENB, RDSN, RDID) are accessed via dedicated opcodes without address overhead.

Key Specifications

Pinout & Package

Package: 16-pin SOIC (Small Outline Integrated Circuit), RoHS-compliant, industrial temperature grade (–40 °C to +85 °C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with FM25V20A-G and AT25SF041-SSHD-B, CY14E256Q5A-SXQ uniquely provides autonomous power-loss data capture via VCAP and HSB, making it the sole choice for systems lacking dedicated power-fail supervision circuitry or requiring guaranteed SRAM-equivalent write performance with nonvolatile persistence.

Availability

CY14E256Q5A-SXQ is available at Aetrix Electronics and suitable for industrial data loggers, PLC configuration storage, medical diagnostic recorders, and avionics health monitors requiring stable component supply and long-term lifecycle support.

Supply support for CY14E256Q5A-SXQ 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-reliability memory and programmable solutions for industrial, automotive, and communications infrastructure.

CY14E256Q5A-SXQ belongs to the nvSRAM product line engineered specifically for deterministic, capacitor-backed data retention in 5 V systems where EEPROM latency or flash endurance limitations are unacceptable.

FAQ

What is the minimum VCAP capacitance required for reliable AutoStore operation?

The minimum VCAP value depends on system VCC droop rate and tSTORE duration specified in the datasheet (typically 20 ms). For CY14E256Q5A-SXQ at 5.5 V, a 47 µF low-ESR tantalum capacitor is recommended to ensure ≥2.7 V hold-up during full STORE. Derating for temperature and aging is required per application-level validation.

Can the HSB pin be used as a general-purpose I/O when Hardware STORE is disabled?

No. The HSB pin is functionally dedicated: when configured as input (for Hardware STORE), it has internal weak pull-up and cannot be driven high externally; when active as output (during STORE/RECALL), it asserts open-drain LOW. It lacks GPIO functionality and must not be tied to other signals without level-shifting or isolation.

Does Software STORE require the device to be in a specific SPI mode or status register state?

Software STORE requires WREN instruction to be issued first to set the Write Enable Latch (WEL) bit. It does not depend on SPI mode (0 or 3) but must be executed after CS assertion and before any other command. The device ignores STORE if WEL = 0 or if block protection bits prevent access to the target address range.

Is the 8-byte serial number writable or factory-programmed only?

The 8-byte serial number is factory-programmed and permanently locked. The WRSN instruction is not supported on CY14E256Q5A-SXQ; attempts to write to the serial number register return status error and leave contents unchanged. This ensures traceability and prevents cloning or rework tampering.