Infineon Technologies CY14B104K-ZS45XI

Overview

CY14B104K-ZS45XI from Cypress Semiconductor is a 4-Mbit nonvolatile SRAM (512 K × 8) integrated with a full-featured real-time clock, 45 ns access time, single 3.0 V (+20%, –10%) supply operation, and QuantumTrap nonvolatile storage enabling 1 million STORE cycles and 20-year data retention. It serves as a drop-in SRAM replacement in industrial control systems requiring persistent time-stamped data logging without external battery backup.

For engineers reviewing the CY14B104K-ZS45XI datasheet, CY14B104K-ZS45XI pinout, CY14B104K-ZS45XI application, or CY14B104K-ZS45XI equivalent, key selection criteria include AutoStore capacitor sizing (VCAP), RTC interrupt configuration (INT pin polarity), ×8 vs ×16 address/data mapping, and HSB-driven hardware STORE timing coordination with system power-fail detection.

Technical Context

The device integrates a standard fast SRAM array with parallel-connected QuantumTrap nonvolatile elements, enabling atomic STORE/RECALL operations without external controllers. All 524,288 bytes transfer simultaneously during STORE (to nv cells) or RECALL (to SRAM), with SRAM read/write inhibited during those cycles.

RTC functionality includes leap-year-corrected calendar, programmable alarm (minutes/hours/days/months), watchdog timer, and dual backup options-capacitor (VCAP + VRTCcap) or battery (VRTCbat). Oscillator calibration and temperature-compensated accuracy are managed internally; no external trimming required.

Key Specifications

Pinout & Package

Package: 44-pin Thin Small Outline Package (TSOP II), 10.16 mm × 18.41 mm × 1.2 mm, RoHS-compliant, lead-free.

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-ZS45XI uniquely combines 45 ns speed, hands-off AutoStore with VCAP, full leap-year RTC, and configurable watchdog - making it optimal for time-critical industrial logging where deterministic power-loss response is mandatory.

Availability

CY14B104K-ZS45XI is available at Aetrix Electronics and suitable for industrial data loggers, PLC memory backup systems, and medical diagnostic devices requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant manufacturing.

Supply support for CY14B104K-ZS45XI 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.

CY14B104K belongs to Cypress's nvSRAM+RTC product line, engineered specifically for systems needing deterministic, battery-free data persistence with integrated timekeeping - eliminating external RTC, backup power, and store-control logic.

FAQ

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

The CY14B104K-ZS45XI requires a 0.1 µF ceramic capacitor on the VCAP pin, rated for ≥10 V, placed within 5 mm of the package. This value ensures sufficient energy to complete one full STORE cycle when VCC drops below 2.7 V, per datasheet Figure 2 and DC Characteristics Table (V_CC = 3.0 V, t_STORE ≤ 20 ms).

Can the RTC operate independently while the SRAM is being accessed?

Yes - the RTC runs continuously from its dedicated oscillator and backup supply (VCAP or VRTCbat), independent of SRAM read/write activity. Clock registers remain readable and writable during SRAM operations, and RTC interrupts (INT) assert asynchronously without blocking memory access.

Is the CY14B104K-ZS45XI pin-compatible with the CY14B104M variant?

No - CY14B104K (512 K × 8) uses A0–A18 and DQ0–DQ7 in a 44-pin TSOP II, while CY14B104M (256 K × 16) requires A0–A17, DQ0–DQ15, BHE/ BLE, and a 54-pin TSOP II. Pin counts, address/data widths, and package footprints differ; direct substitution is not possible without PCB redesign.

How is the watchdog timer configured and cleared?

The watchdog is enabled via RTC register WDTEN (bit 7 of Flags Register). Timeout period is set using WDT[2:0] bits (125 ms to 16 s). It clears automatically on any SRAM write or RTC register write; no dedicated feed sequence is needed. Timeout asserts INT and can be masked via IMR register.