Infineon Technologies STK14C88-NF35ITR

Overview

STK14C88-NF35ITR from Cypress Semiconductor is a 32K × 8 (256 Kb) nonvolatile static RAM with AutoStore functionality, operating at 35 ns read/write cycle time, single 5V ±10% supply, and 100-year data retention. It integrates Quantum Trap nonvolatile storage per cell, enabling automatic STORE on power loss and RECALL on power-up, used in industrial control systems requiring persistent memory without backup batteries.

For engineers reviewing the STK14C88-NF35ITR datasheet, STK14C88-NF35ITR pinout, STK14C88-NF35ITR application, or STK14C88-NF35ITR equivalent, key selection criteria include hardware/software-controlled STORE/RECALL timing, HSB signaling behavior, VCAP capacitor interface, and compatibility with legacy SRAM bus protocols in mission-critical embedded logging and configuration storage.

Technical Context

The STK14C88-NF35ITR implements monolithic nvSRAM architecture with dual-mode operation: standard SRAM access (address/data/control pins fully compatible with JEDEC 32-pin SOIC SRAMs) and nonvolatile management via dedicated HSB and VCAP pins. Its STORE operation transfers SRAM contents to Quantum Trap cells within 10 ms, triggered either by power-loss detection or external HSB assertion.

It supports three operational modes-AutoStore (automatic STORE on VCC drop), Hardware STORE (HSB-driven), and Software STORE (via address/command sequence)-with independent RECALL activation on power-up or software command. All modes preserve unlimited SRAM read/write endurance while guaranteeing ≥1 million STORE cycles and zero data loss during brownout events down to 2.7V.

Key Specifications

Pinout & Package

STK14C88-NF35ITR uses a 32-pin 300-mil SOIC package (RoHS-compliant), pin-compatible with industry-standard 32K×8 SRAMs. VCAP requires external 4.7 µF tantalum capacitor connected between pin 28 and ground for reliable AutoStore operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK14CA8-35I and FM1808-35-TG, the STK14C88-NF35ITR uniquely delivers true hands-off AutoStore with integrated power-loss sensing in a standard SOIC package-critical for cost-sensitive industrial designs where board space and assembly compatibility constrain alternatives.

Availability

STK14C88-NF35ITR is available at Aetrix Electronics and suitable for industrial PLCs, medical infusion pumps, and smart electricity meters requiring stable component supply with guaranteed long-term availability and RoHS-compliant manufacturing.

Supply support for STK14C88-NF35ITR 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 U.S.-based 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 applications where maintenance-free, long-life nonvolatile storage is essential under harsh electrical conditions.

FAQ

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

The STK14C88-NF35ITR requires a minimum 4.7 µF tantalum capacitor on VCAP (pin 28) to sustain the 10 ms STORE operation during VCC collapse. Lower values risk incomplete STORE; higher values extend hold-up time but increase board area and cost. Ceramic capacitors are not recommended due to insufficient energy density and voltage derating effects.

Does STK14C88-NF35ITR support byte-level writes like standard SRAM?

Yes-STK14C88-NF35ITR performs true byte-level SRAM writes using standard E/W/G control signals. The nonvolatile STORE operation always saves the entire 32K-byte array, but SRAM access remains identical to conventional parallel SRAMs, including partial-word writes and random-address updates without block erasure.

Can HSB be left unconnected in applications that only use AutoStore mode?

Yes-HSB may be left floating or tied to VCC via a weak pull-up (10 kΩ) when only AutoStore (power-loss-triggered) and power-up RECALL are used. The internal weak pull-up ensures HSB remains high during normal operation; external connection is required only for hardware-initiated STORE or status monitoring.

Is STK14C88-NF35ITR compatible with 3.3V I/O systems?

No-STK14C88-NF35ITR is strictly a 5V-only device with TTL/CMOS input thresholds referenced to 5V (VIH = 2.2V min, VIL = 0.8V max). Interfacing with 3.3V microcontrollers requires level-shifting on all control and data lines; it does not support mixed-voltage operation or 3.3V standby modes.