Infineon Technologies STK14D88-NF45I

Overview

STK14D88-NF45I from Cypress Semiconductor is a 32K × 8 (256 Kb) nonvolatile static RAM with integrated Quantum Trap storage, delivering 45 ns read/write cycle time, automatic power-loss STORE and power-up RECALL, and unlimited SRAM endurance. It operates from a single 3.0V ±10% supply and supports industrial temperature range (–40°C to +85°C) in 32-pin SOIC package. Used in metering, industrial PLCs, and network equipment requiring persistent data retention without battery backup.

For engineers reviewing the STK14D88-NF45I datasheet, STK14D88-NF45I pinout, STK14D88-NF45I application, or STK14D88-NF45I equivalent, this page provides verified timing parameters, validated AutoStore/RECALL behavior, confirmed VCAP capacitor requirements, and real-world implementation constraints for fail-safe memory retention in embedded control systems.

Technical Context

The STK14D88-NF45I integrates a standard fast SRAM array (512 × 512) with monolithic Quantum Trap nonvolatile elements per cell. Its STORE operation triggers automatically when VCC drops below 2.65 V, using energy stored on the external VCAP capacitor (17–120 µF, 5 V rated) to complete a 12.5 ms nonvolatile write.

RECALL occurs at power-up once VCC exceeds 2.65 V, restoring data in ≤20 ms. Both operations are also software-controllable via HSB pin assertion or command sequences, and hardware-initiated by pulling HSB low. The device ignores all SRAM access during STORE/RECALL cycles.

Key Specifications

Pinout & Package

STK14D88-NF45I is packaged in a 32-pin Small Outline Integrated Circuit (SOIC) with 0.3 inch body width and standard JEDEC MS-012AC footprint. Pin 1 is marked by notch or dot; pin numbering follows counterclockwise convention from top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK14C88-35I, the STK14D88-NF45I trades 10 ns slower access for higher tolerance to voltage droop during STORE initiation; versus FM24CL64-G, it preserves parallel bus performance and fixed 12.5 ms STORE duration-critical for deterministic power-fail response in real-time control.

Availability

STK14D88-NF45I is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, and network infrastructure requiring stable component supply, long-lifecycle support, and guaranteed nonvolatile data retention without battery dependency.

Supply support for STK14D88-NF45I 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 markets.

The STK14D88 belongs to Cypress's nvSRAM product line, engineered specifically to replace battery-backed SRAM in mission-critical systems where maintenance-free, long-term data persistence is mandatory.

FAQ

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

The STK14D88-NF45I requires a minimum 17 µF, 5 V-rated capacitor between VCAP and VSS to guarantee successful STORE during worst-case VCC dropout profiles. Lower values risk incomplete data transfer to Quantum Trap cells, especially at elevated temperatures or high VCC slew rates. Recommended value is 47 µF for margin across industrial temperature range.

Can STK14D88-NF45I be used as a drop-in replacement for standard SRAM?

Yes-electrically and pin-compatible with standard 32K×8 SRAMs (e.g., AS6C4008, CY62167), provided the VCAP capacitor is added and HSB is left unconnected or pulled high. All control signals (E, W, G) and timing parameters match 45 ns SRAM specifications, enabling seamless integration into existing PCB layouts.

How does the device behave during VCC brownout below 2.65 V?

When VCC falls to ≤2.65 V, the internal power-fail detector triggers AutoStore: SRAM contents are transferred to Quantum Trap cells using energy from VCAP. During this 12.5 ms STORE window, all read/write cycles are ignored, and HSB goes low. The device remains unresponsive until RECALL completes at next power-up.

Is software-controlled STORE functionally identical to AutoStore?

Yes-the same Quantum Trap write mechanism is used. Software STORE (via HSB assertion or command) executes identically to AutoStore in duration (12.5 ms), power consumption (ICC2 = 3 mA), and data integrity. The key difference is deterministic initiation: software STORE allows saving state before controlled shutdown, while AutoStore responds only to power loss.