Infineon Technologies CY14B104K-ZS25XIT

Overview

CY14B104K-ZS25XIT from Cypress Semiconductor is a 4-Mbit nonvolatile SRAM (512 K × 8) with integrated real-time clock, AutoStore capability, and watchdog timer. It operates at 3.0 V ±10%, delivers 25 ns access time, supports infinite SRAM read/write cycles, and retains data for 20 years without power. It is used in industrial control systems requiring persistent time-stamped memory during unexpected power loss.

For engineers reviewing the CY14B104K-ZS25XIT datasheet, CY14B104K-ZS25XIT pinout, CY14B104K-ZS25XIT application, or CY14B104K-ZS25XIT equivalent, key selection criteria include nvSRAM+RTC integration, capacitor-backed AutoStore timing, HSB-controlled hardware store latency, and TSOP II package compatibility with legacy 8-bit bus interfaces.

Technical Context

The device integrates a standard SRAM array with parallel QuantumTrap nonvolatile elements, enabling simultaneous STORE/RECALL across all 524,288 bytes. STORE is triggered by power-down (via VCAP), software command, or HSB assertion; RECALL occurs automatically on power-up or via software.

Its RTC subsystem includes leap-year correction, programmable alarm (minutes/hours/days/months), watchdog timer, and dual backup options (VCAP capacitor or VRTCbat battery). The oscillator uses an external 32.768 kHz crystal connected to Xin/Xout pins, with internal calibration support.

Key Specifications

Pinout & Package

Package: 44-pin Thin Small Outline Package (TSOP II), RoHS-compliant, 0.8 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK14CA8-NL35I and FM31L273-G, CY14B104K-ZS25XIT uniquely combines 25 ns speed, capacitor-backed AutoStore, and 4-Mbit density in a 44-pin TSOP - making it optimal for space-constrained industrial controllers needing fast, reliable, battery-free power-loss recovery.

Availability

CY14B104K-ZS25XIT is available at Aetrix Electronics and suitable for industrial data loggers, smart energy meters, PLC I/O modules, and medical diagnostic equipment requiring stable component supply and long-term lifecycle support.

Supply support for CY14B104K-ZS25XIT 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 mixed-signal ICs for industrial, automotive, and IoT applications, with expertise in nonvolatile memory and timing solutions.

This part belongs to the nvSRAM+RTC product line, engineered to replace discrete SRAM+RTC+battery designs with monolithic, qualification-ready components for mission-critical power-loss resilience.

FAQ

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

The datasheet specifies a 0.1 µF ceramic capacitor on the VCAP pin. This value ensures sufficient charge to complete a full STORE operation when VCC drops below VSWITCH (typically 2.0 V). Using a smaller capacitor risks incomplete STORE and data corruption; larger values extend hold-up time but do not improve reliability beyond specification.

Can the RTC operate independently while the nvSRAM is being written?

Yes. The RTC runs continuously from its dedicated backup supply (VCAP or VRTCbat) and is fully independent of SRAM read/write operations. Clock counting, alarm generation, and watchdog timing proceed uninterrupted during active memory access or STORE/RECALL cycles.

Is the CY14B104K-ZS25XIT pin-compatible with earlier CY14B104K variants?

Yes. The -ZS25XIT suffix denotes the 44-pin TSOP II package with 25 ns access time and industrial temperature range. It shares identical pinout, signal definitions, and timing behavior with other CY14B104K variants in the same package, enabling drop-in replacement in existing designs.

How does the HSB pin behave during a software-initiated STORE?

During software STORE, HSB is driven LOW by the device to indicate busy status, just as during AutoStore or hardware STORE. It remains LOW for tHHHD (≤100 µs) after completion, then returns HIGH via internal 100 kΩ pull-up. External pull-up is optional but recommended for noise immunity in noisy industrial environments.