Infineon Technologies STK11C88-SF25

Overview

STK11C88-SF25 from Cypress Semiconductor is a 256 Kbit (32K × 8) nonvolatile static RAM with integrated QuantumTrap™ nvSRAM technology, operating at 5 V ±10%, offering 25 ns access time, automatic hardware RECALL on power-up, and software-initiated STORE/RECALL. It functions as a drop-in replacement for standard SRAM in systems requiring persistent data retention without backup batteries-e.g., industrial PLCs preserving configuration during brownouts.

For engineers reviewing the STK11C88-SF25 datasheet, STK11C88-SF25 pinout, STK11C88-SF25 application, or STK11C88-SF25 equivalent, key selection criteria include its 100-year data retention, unlimited RECALL cycles, 1M STORE endurance, 28-pin SOIC package compatibility, and deterministic software STORE/RECALL address sequences.

Technical Context

The STK11C88-SF25 integrates a standard 32K × 8 SRAM array with parallel nonvolatile storage cells using Cypress's QuantumTrap technology-each memory cell contains both volatile and nonvolatile elements. Data persistence relies on charge trapping in nitride-based layers, not external capacitors or batteries.

STORE and RECALL operations are strictly controlled via six-cycle CE-controlled READ sequences to dedicated addresses (e.g., 0x0FC0 initiates STORE; 0x0C63 initiates RECALL), with hardware RECALL triggered automatically when VCC exceeds VSWITCH after power-up or brownout recovery.

Key Specifications

Pinout & Package

28-pin SOIC (300 mil body width), RoHS-compliant surface-mount package with standard footprint for automated assembly and thermal reliability up to 85°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK11C68-SF25, the STK11C88-SF25 doubles capacity without changing layout or timing; versus FM24CL16B, it retains full SRAM compatibility but requires precise address-sequence control and higher VCC.

Availability

STK11C88-SF25 is available at Aetrix Electronics and suitable for industrial PLCs, medical infusion pumps, point-of-sale terminals, and telecom base station timing modules requiring stable component supply and long-term lifecycle support.

Supply support for STK11C88-SF25 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 mixed-signal ICs for industrial, automotive, and communications infrastructure.

The STK11C88 belongs to Cypress's SoftStore® nvSRAM product line, engineered specifically to replace battery-backed SRAM in mission-critical systems where maintenance-free, long-term data retention is mandatory.

FAQ

What triggers automatic RECALL on power-up?

Automatic RECALL activates when VCC rises above the internal VSWITCH threshold (~3.0 V typical) after power-down or brownout. The chip detects this transition and initiates a hardware RECALL cycle lasting tHRECALL (≤15 ms max), restoring nonvolatile data to SRAM before host access is possible. No external signal or firmware action is required.

Can STORE and RECALL be interrupted by normal SRAM accesses?

No-STORE and RECALL operations lock the device: all I/O pins enter high-impedance state, and external address/data/control signals are ignored until completion. Any intervening CE/WE/OE transitions abort the sequence. The six-address software protocol must execute consecutively without interruption to succeed.

Is the STK11C88-SF25 pin-compatible with standard 28-pin SOIC SRAMs?

Yes-STK11C88-SF25 uses identical 28-pin SOIC pinout and electrical signaling (TTL/CMOS-compatible inputs, 3-state outputs) as industry-standard 32K × 8 SRAMs like the AS6C4008 or CY62256. No PCB redesign is needed for drop-in replacement, though firmware must implement STORE/RECALL sequences.

Does the device require external components for nonvolatile operation?

No external capacitors, batteries, or regulators are required. QuantumTrap technology embeds nonvolatility at the cell level. A 0.1 µF ceramic bypass capacitor between VCC and VSS is mandatory for noise suppression but serves general power integrity-not data retention.