Infineon Technologies CY14B104M-ZSP45XI

Overview

CY14B104M-ZSP45XI from Cypress Semiconductor is a 4-Mbit nonvolatile SRAM (256 K × 16) with integrated real-time clock, AutoStore capability, and watchdog timer. It operates at 3.0 V ±10%, delivers 45 ns access time, supports infinite SRAM read/write cycles, and retains data for 20 years. It is used in industrial control systems requiring persistent time-stamped memory during power loss.

For engineers reviewing the CY14B104M-ZSP45XI datasheet, CY14B104M-ZSP45XI pinout, CY14B104M-ZSP45XI application, or CY14B104M-ZSP45XI equivalent, key selection considerations include ×16 bus width support, VCAP-backed AutoStore timing, RTC alarm interrupt configuration, and HSB-controlled hardware STORE sequencing.

Technical Context

The device integrates a 256 K × 16 SRAM array with QuantumTrap nonvolatile storage and a full-featured RTC subsystem including leap-year tracking, programmable oscillator calibration, and minute/hour/day/month alarm intervals. The RTC uses either VRTCcap (0.1 µF capacitor) or VRTCbat (battery) backup.

STORE operations occur via software address sequence, HSB pin assertion, or automatic power-down detection using charge stored on the VCAP pin. RECALL occurs automatically at power-up or via software command. The HSB pin serves dual role: input to trigger STORE and open-drain output indicating busy status during STORE/RECALL.

Key Specifications

Pinout & Package

Package: 54-pin Thin Small Outline Package (TSOP II), RoHS-compliant, industrial temperature range (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with STK14CA8-NL35I and FM31L273-G, CY14B104M-ZSP45XI uniquely combines ×16 bus support, hands-off AutoStore, and full RTC feature set - making it optimal for 16-bit industrial controllers needing zero-intervention data preservation and precise timekeeping.

Availability

CY14B104M-ZSP45XI is available at Aetrix Electronics and suitable for industrial PLC data logging, medical infusion pump timestamping, and smart meter firmware state save requiring stable component supply and guaranteed 20-year data retention.

Supply support for CY14B104M-ZSP45XI 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 emphasis on nonvolatile memory and timing solutions.

CY14B104M belongs to the nvSRAM+RTC product line, engineered to replace battery-backed SRAM and discrete RTCs in mission-critical systems where data integrity and time accuracy must survive uncontrolled power loss.

FAQ

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

The CY14B104M-ZSP45XI requires a minimum 4.7 µF tantalum or ceramic capacitor on the VCAP pin to ensure successful STORE completion during VCC dropout. This value is specified in the DC Electrical Characteristics table (page 16 of Rev. AD datasheet) and accounts for worst-case voltage droop, internal regulator efficiency, and QuantumTrap write energy. Using less capacitance risks incomplete STORE and data corruption.

Can the RTC operate without external crystal or backup power?

No. The RTC requires either a 32.768 kHz crystal connected between Xin and Xout pins, plus either VRTCcap (0.1 µF capacitor) or VRTCbat (coin cell) for backup power. If neither backup source is connected, the RTC stops counting upon VCC removal and loses time - though the nvSRAM retains stored data. The RTC will not function with only VCC present.

How does the HSB pin behave during simultaneous SRAM write and STORE request?

When HSB is pulled LOW during an ongoing SRAM write, the device waits tDELAY (max 100 ns) for that write to complete before initiating STORE. Any new write requests issued after HSB goes LOW are blocked until HSB returns HIGH. This ensures data coherency: the last completed write is preserved in SRAM before transfer to QuantumTrap.

Is the CY14B104M-ZSP45XI pin-compatible with earlier CY14B104M variants?

Yes - the ZSP45XI suffix denotes 45 ns access time in 54-pin TSOP II package, fully compatible with other CY14B104M versions sharing the same package type (e.g., ZSP25XI). Pin functions, voltage levels, timing parameters, and register maps are identical; only access time and ordering code differ. No PCB redesign is needed when upgrading within the same package family.