Infineon Technologies CY14E256Q5A-SXQT

Overview

CY14E256Q5A-SXQT 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 via SPI. It performs automatic STORE on power-down using an external capacitor (VCAP), supports hardware STORE via HSB pin, and delivers infinite SRAM write cycles with 20-year data retention at 85 °C - used in industrial PLCs for real-time parameter backup.

For engineers reviewing the CY14E256Q5A-SXQT datasheet, CY14E256Q5A-SXQT pinout, CY14E256Q5A-SXQT application, or CY14E256Q5A-SXQT equivalent, key selection criteria include VCAP-assisted AutoStore timing, HSB pin behavior during STORE/RECALL, SPI mode 0/3 compatibility, and 1/4–full array software block protection.

Technical Context

This nvSRAM integrates SRAM and QuantumTrap nonvolatile storage per cell, enabling zero-cycle-delay reads/writes to SRAM while isolating endurance-limited STORE/RECALL operations to dedicated nonvolatile elements. It uses SONOS-based QuantumTrap cells with 1 million STORE cycles and 20-year retention at 85 °C.

SPI interface supports dual-speed operation: 40 MHz standard READ/WRITE and 104 MHz FAST_READ with dummy byte; supports modes 0 (CPOL=0, CPHA=0) and 3 (CPOL=1, CPHA=1); includes status register (RDSR/WRSR), serial number (8-byte), device ID, and SLEEP instruction for ultra-low-power standby.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY14B256Q5A-SXIT, CY14E256Q5A-SXQT provides integrated VCAP-based AutoStore for simpler 5 V designs; versus FM25V20A-G, it trades unlimited endurance for higher density and proven QuantumTrap retention at elevated temperature.

Availability

CY14E256Q5A-SXQT is available at Aetrix Electronics and suitable for industrial PLCs, medical calibration systems, automotive body controllers, and smart energy meters requiring stable component supply and guaranteed long-term data retention.

Supply support for CY14E256Q5A-SXQT 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 IoT applications.

CY14E256Q belongs to the nvSRAM product line, engineered specifically for systems needing instant-on SRAM performance with fail-safe nonvolatile backup - eliminating battery dependencies and EEPROM wear-out limitations.

FAQ

What is the function of the VCAP pin, and what capacitor value is required?

The VCAP pin supplies temporary power to complete the STORE operation during VCC dropout. A minimum 4.7 µF tantalum or ceramic capacitor rated ≥10 V must be placed between VCAP and VSS, with low-ESR (<1 Ω) and short PCB traces. No connection is allowed if AutoStore is disabled.

How does Hardware STORE differ from Software STORE in timing and reliability?

Hardware STORE is initiated by a LOW pulse on HSB and begins immediately upon pin assertion, independent of SPI bus activity. Software STORE requires issuing the STORE opcode over SPI and is subject to bus arbitration. Both use identical QuantumTrap programming sequences and offer equal data integrity; HSB offers deterministic timing for safety-critical power-loss events.

Can CY14E256Q5A-SXQT operate in SPI mode 1 or 2?

No - this device only supports SPI mode 0 (CPOL = 0, CPHA = 0) and mode 3 (CPOL = 1, CPHA = 1). Attempting mode 1 or 2 will result in incorrect data sampling due to mismatched clock polarity and phase alignment with SI/SO timing requirements.

Is the 8-byte serial number user-programmable, and how is it accessed?

The 8-byte serial number is factory-programmed and read-only. It is accessed via RDSN (Serial Number Read) instruction, which outputs the full 8-byte sequence on SO after opcode and address transmission. WRSN (Write Serial Number) is not supported - the number cannot be altered in the field or during programming.