Infineon Technologies STK14C88-3NF45ITR

Overview

STK14C88-3NF45ITR from Cypress Semiconductor is a 256 Kbit (32K × 8) nonvolatile SRAM with AutoStore functionality, QuantumTrap nonvolatile cell architecture, 45 ns access time, single 3.3V ±0.3V supply, and industrial temperature range (–40°C to +85°C). It serves as a drop-in SRAM replacement in systems requiring persistent data retention across power cycles, such as industrial PLCs and telecom control cards.

For engineers reviewing the STK14C88-3NF45ITR datasheet, STK14C88-3NF45ITR pinout, STK14C88-3NF45ITR application, or STK14C88-3NF45ITR equivalent, key selection criteria include VCAP capacitor sizing (68–220 µF), HSB hardware store timing (tDELAY), software STORE/RECALL address sequence integrity, and compatibility with 32-pin SOIC footprint and 3.3V I/O logic levels.

Technical Context

The STK14C88-3NF45ITR integrates parallel SRAM and QuantumTrap nonvolatile storage per cell, enabling simultaneous STORE/RECALL of all 32,768 bytes. Its dual-mode operation supports automatic power-loss STORE via VCAP discharge and software-initiated STORE/RECALL using six-address CE-controlled READ sequences.

Hardware STORE is triggered by pulling HSB low, with built-in tDELAY to complete pending writes; RECALL occurs automatically at power-up when VCC exceeds VSWITCH. The device inhibits SRAM access during STORE/RECALL cycles and supports unlimited SRAM read/write endurance alongside 1,000,000 STORE cycles and 100-year data retention.

Key Specifications

Pinout & Package

STK14C88-3NF45ITR is housed in a 32-pin Small Outline Integrated Circuit (SOIC) package with 300-mil body width and standard JEDEC MS-012AC footprint. Pin spacing is 0.050 inch (1.27 mm), compatible with automated SMT placement and reflow profiles for lead-free assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK14C88-3NF45ITR, STK14CA8-3AF45I offers identical electrical behavior in a through-hole format but sacrifices surface-mount scalability, while AS1C32K8P-35TIN trades STORE endurance and proven field reliability for unit cost reduction in less demanding environments.

Availability

STK14C88-3NF45ITR is available at Aetrix Electronics and suitable for industrial PLCs, telecom line cards, and medical diagnostic devices requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for STK14C88-3NF45ITR 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 emphasis on mixed-signal integration and long-term product support.

The STK14C88 series belongs to Cypress's nvSRAM product line, engineered specifically to replace battery-backed SRAM in mission-critical systems where maintenance-free, high-endurance, fast nonvolatile storage is essential.

FAQ

What is the minimum VCAP capacitor value required for reliable AutoStore operation?

The STK14C88-3NF45ITR requires a minimum 68 µF tantalum or aluminum electrolytic capacitor rated at 4.7V and ±20% tolerance on the VCAP pin. Values below this threshold may fail to sustain the full STORE operation under worst-case VCC droop rates exceeding 20 µs/V, resulting in partial or corrupted nonvolatile writes.

Can STK14C88-3NF45ITR be used in place of standard SRAM without circuit modification?

Yes - it is a pin- and function-compatible drop-in replacement for 32K × 8 SRAMs in 32-pin SOIC packages. However, VCAP must be populated with a correctly rated capacitor, and HSB should be left unconnected or pulled up if unused. No changes to address/data/control timing are needed beyond verifying tAA = 45 ns meets system setup/hold margins.

How does the software STORE sequence prevent accidental activation?

The six-address CE-controlled READ sequence (0x0E38 → 0x31C7 → 0x03E0 → 0x3C1F → 0x303F → 0x0FC0) requires exact order, no intervening writes, and CE-driven timing. Any deviation - including OE transitions, address glitches, or concurrent writes - aborts the sequence, ensuring STORE cannot occur from spurious bus activity or software errors.

Is STK14C88-3NF45ITR recommended for new designs?

No - Cypress documentation explicitly marks this part as "Not Recommended for New Designs." While fully supported for existing production and repair, designers should evaluate Infineon's newer nvSRAM families (e.g., CY14B108QN) for enhanced endurance, lower voltage operation, and extended lifecycle roadmaps before initiating new projects.