Infineon Technologies STK11C88-SF45ITR

Overview

STK11C88-SF45ITR from Cypress Semiconductor is a 256 Kbit (32K × 8) nonvolatile static RAM with QuantumTrap® technology, functioning as a drop-in replacement for standard SRAMs while retaining data without backup power. It delivers 45 ns access time, operates on single 5V ±10% supply, and supports software-initiated STORE/RECALL plus automatic hardware RECALL on power-up - used in industrial PLCs, metering systems, and real-time control modules requiring persistent state retention.

For engineers reviewing the STK11C88-SF45ITR datasheet, STK11C88-SF45ITR pinout, STK11C88-SF45ITR application, or STK11C88-SF45ITR equivalent, key selection criteria include nvSRAM endurance (1M STORE cycles), 100-year data retention, 28-pin SOIC package compatibility, and deterministic software address-sequence initiation of nonvolatile operations.

Technical Context

The STK11C88 integrates volatile SRAM and nonvolatile QuantumTrap cells per bit, enabling independent read/write cycling (unlimited) and controlled data transfer between domains. Its dual-mode operation includes standard SRAM access and atomic STORE/RECALL via six-address CE-controlled READ sequences - no external capacitors or batteries required.

Hardware RECALL triggers automatically when VCC rises above VSWITCH after brownout or power cycle, completing in tHRECALL (max 20 ms). STORE inhibits during low-VCC conditions (VCC < VSWITCH), preventing corruption, and all control inputs (CE, WE, OE) are TTL/CMOS compatible with defined VIH/VIL thresholds.

Key Specifications

Pinout & Package

STK11C88-SF45ITR uses a 28-pin Small Outline Integrated Circuit (SOIC) package with 300 mil body width, RoHS-compliant lead finish, and standard JEDEC MO-012AC footprint.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK11C88-SF45ITR, the SF25ITR variant trades lower power for speed, while the DS1248W relies on electrochemical backup instead of quantum tunneling - making STK11C88-SF45ITR the only RoHS-compliant, battery-free solution with guaranteed 100-year retention and deterministic software control.

Availability

STK11C88-SF45ITR is available at Aetrix Electronics and suitable for industrial automation, smart metering, and railway signaling applications requiring stable component supply and long-term lifecycle support.

Supply support for STK11C88-SF45ITR 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, with headquarters in San Jose, CA.

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-life nonvolatility is mandatory.

FAQ

What triggers automatic RECALL on power-up?

Automatic RECALL initiates when VCC rises above the internal VSWITCH threshold (~3.0 V) after power loss or brownout. The device latches the RECALL request during low-VCC and executes it once stable supply is detected, completing within tHRECALL (≤20 ms). No external signal or firmware action is needed - this is fully hardware-managed.

Can STORE and RECALL be performed while the system is running?

Yes - both operations are software-initiated via six consecutive CE-controlled READs to specific addresses (0x0E38 through 0x0FC0 for STORE; 0x0C63 for RECALL). During execution, the I/O pins are tristated and the SRAM is inaccessible. Total duration is tSTORE (max 25 ms) or tRECALL (max 20 ms), as specified in the datasheet.

Is the STK11C88-SF45ITR pin-compatible with standard 28-pin SOIC SRAMs?

Yes - it uses identical 28-pin SOIC (300 mil) pinout and electrical interface as industry-standard 32K × 8 SRAMs (e.g., AS6C4008, IS61LV25616). Address, data, and control signals map one-to-one; no PCB redesign is required for drop-in replacement in existing 5V systems.

Does the device require external components for nonvolatile operation?

No - STK11C88-SF45ITR requires only a 0.1 µF ceramic bypass capacitor between VCC and VSS, as mandated for all high-speed CMOS memory. Unlike battery-backed SRAMs, it contains no consumable elements and needs no external energy source, supercapacitor, or charge circuitry for data retention.