Infineon Technologies CY14B104NA-ZS45XET

Overview

CY14B104NA-ZS45XET from Cypress Semiconductor is an automotive-grade 4-Mbit (256K × 16) non-volatile SRAM with QuantumTrap technology, operating at 45 ns access time and single 3.3 V supply. It integrates volatile SRAM and non-volatile storage in each cell, enabling automatic STORE on power-down via VCAP capacitor and software- or hardware-triggered RECALL. Used in engine control units for fault-code retention during ignition cycling.

For engineers reviewing the CY14B104NA-ZS45XET datasheet, CY14B104NA-ZS45XET pinout, CY14B104NA-ZS45XET application, or CY14B104NA-ZS45XET equivalent, key selection criteria include AutoStore timing (tSTORE = 10 ms max), HSB pin behavior during STORE/RECALL, VCAP capacitance requirement (0.1 µF), and Automotive-E temperature rating (–40 °C to +125 °C).

Technical Context

The CY14B104NA-ZS45XET implements a dual-cell architecture: standard fast SRAM for active read/write and parallel QuantumTrap non-volatile elements per cell. STORE transfers data from SRAM to non-volatile storage; RECALL restores it - both operations inhibit SRAM access.

AutoStore initiates when VCC drops below VSWITCH (2.7 V min), using charge stored on external VCAP (0.1 µF). Hardware STORE is triggered by pulling HSB low; software STORE uses a six-address read sequence (0x4E38 → 0xB1C7 → 0x83E0 → 0x7C1F → 0x703F → 0x8FC0). HSB serves as both input request and open-drain busy indicator.

Key Specifications

Pinout & Package

Package: 44-pin TSOP II (Type II), RoHS-compliant, surface-mount. Pin pitch: 0.8 mm. Body size: 12.0 mm × 20.0 mm × 1.2 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar non-volatile SRAM applications.

Compared with STK14C88-45I and FM24V10-G, the CY14B104NA-ZS45XET uniquely combines 4-Mbit density, hardware STORE triggering via HSB, and capacitor-backed AutoStore - making it optimal for ASIL-B/C systems requiring deterministic, low-latency non-volatile state capture without host CPU involvement.

Availability

CY14B104NA-ZS45XET is available at Aetrix Electronics and suitable for engine control units, ADAS domain controllers, and electric power steering modules requiring stable component supply across extended automotive lifecycles.

Supply support for CY14B104NA-ZS45XET 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 automotive, industrial, and IoT applications.

The CY14B series targets automotive electronics needing deterministic non-volatile data retention without batteries or complex firmware - specifically engineered for ECU, telematics, and safety-critical subsystems operating up to 125 °C.

FAQ

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

The CY14B104NA-ZS45XET requires a minimum 0.1 µF X7R ceramic capacitor on the VCAP pin. This value ensures ≥10 ms STORE duration under worst-case VCC dropout conditions (2.7 V to 0 V at 100 mV/µs). Larger values extend margin but do not reduce tSTORE; undersized capacitors risk incomplete STORE and data corruption.

Can the HSB pin be left unconnected if hardware STORE is not used?

Yes - the HSB pin may be left floating if hardware STORE triggering and busy indication are unused. The internal 100 kΩ weak pull-up ensures it remains HIGH during normal operation. However, if the system monitors HSB for STORE status, a 4.7 kΩ external pull-up to VCC is recommended for noise immunity in high-EMI automotive environments.

How does the CY14B104NA-ZS45XET handle simultaneous SRAM access during STORE initiation?

When HSB is pulled LOW or VCC drops below VSWITCH, ongoing SRAM writes complete within tDELAY (max 150 ns), then all SRAM access is inhibited until STORE finishes. Reads and writes requested after HSB assertion are blocked; the device drives HSB LOW continuously until tSTORE (max 10 ms) expires and SRAM becomes accessible again.

Is the software STORE sequence compatible with burst read modes or cache-line fetches?

No - the six-address software STORE sequence (0x4E38 → 0xB1C7 → … → 0x8FC0) must use discrete, non-burst, CE- or OE-controlled reads with WE held HIGH. Burst or prefetch operations will interrupt the sequence, aborting STORE initiation. Each address must be accessed individually with stable control timing per datasheet AC specs (tACE, tDOE).