Infineon Technologies STK14C88-NF45

Overview

STK14C88-NF45 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 5V ±10% supply and retains data for 100 years without power. Used in industrial control systems requiring persistent memory across unexpected power interruptions.

For engineers reviewing the STK14C88-NF45 datasheet, STK14C88-NF45 pinout, STK14C88-NF45 application, or STK14C88-NF45 equivalent, key selection criteria include AutoStore timing (10 ms STORE duration), HSB-controlled hardware STORE initiation, VCAP capacitor dependency, and compatibility with standard SRAM bus protocols in legacy industrial controllers.

Technical Context

The STK14C88 integrates SRAM and nonvolatile Quantum Trap cells monolithically-each memory cell includes both volatile and nonvolatile storage elements. STORE transfers data from SRAM to nonvolatile cells upon power loss detection or external HSB assertion; RECALL restores data on power-up or via software command.

It supports dual-mode operation: standard SRAM access (E/G/W controlled) and hardware-triggered nonvolatile STORE (HSB low pulse). The device requires an external VCAP capacitor (typically 4.7 µF tantalum) to sustain STORE during VCC collapse, and uses weak internal pull-up on HSB for default high-idle behavior.

Key Specifications

Pinout & Package

STK14C88-NF45 is packaged in a 32-pin 300-mil SOIC (RoHS-compliant), pin-compatible with industry-standard 32-pin SRAM footprints. Pin functions are electrically and physically defined per Cypress Document 001-52038 Rev. *B.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK14C88-NF45, STK14CA8-NF45 offers faster STORE and lower quiescent power but shares identical footprint and interface; FM1808-40-SG removes VCAP dependency but sacrifices autonomous power-loss protection and industrial temperature support.

Availability

STK14C88-NF45 is available at Aetrix Electronics and suitable for industrial control systems, medical instrumentation, and avionics subsystems requiring stable component supply and long-term obsolescence management.

Supply support for STK14C88-NF45 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 fabless semiconductor company specializing in memory, microcontrollers, and connectivity solutions for industrial, automotive, and consumer markets.

The STK14C88 belongs to Cypress's nvSRAM product line, designed specifically to replace battery-backed SRAM in mission-critical systems where maintenance-free, long-term data retention is mandatory.

FAQ

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

The VCAP pin connects to an external capacitor (typically 4.7 µF solid tantalum) that supplies energy during VCC collapse to complete the 10 ms STORE operation. Cypress specifies minimum capacitance and ESR limits in Document 001-52038: 4.7 µF ±20%, ESR ≤ 3 Ω at 100 kHz. Undersized VCAP causes STORE corruption or failure.

Can STK14C88-NF45 be used without connecting HSB?

Yes-HSB is optional. When left unconnected, its internal weak pull-up holds it high, disabling hardware STORE initiation. AutoStore still functions on power loss, and software STORE/RECALL remains fully operational via reserved address writes. HSB is only required for externally triggered STORE events.

How does the device handle simultaneous SRAM access and STORE operations?

The STK14C88 blocks SRAM access during STORE: when HSB is pulled low or power drops, E/G/W are ignored and DQ pins go high-impedance for the full 10 ms STORE duration. Any ongoing SRAM cycle is terminated, and the device enters standby until STORE completes and HSB returns high.

Is STK14C88-NF45 RoHS-compliant, and what is its lead time status?

Yes-STK14C88-NF45 is RoHS-compliant per its 32-pin 300-mil SOIC package designation in the datasheet. As a mature industrial-grade component, it is actively stocked by Aetrix Electronics with standard lead times of 2–4 weeks; extended-volume orders qualify for consignment stocking and lifecycle extension support.