Cypress Semiconductor Corp CY15B128Q-SXAT

Overview

CY15B128Q-SXAT from Cypress Semiconductor is a 128-Kbit (16K × 8) automotive-grade serial F-RAM with SPI interface, operating from 2.0 V to 3.6 V over –40 °C to +85 °C. It delivers NoDelay™ writes at up to 40 MHz, supports SPI modes 0 and 3, and provides 10¹⁴ read/write endurance with 151-year data retention - deployed in vehicle telematics log buffers and ADAS event recorders where rapid nonvolatile writes are critical.

For engineers reviewing the CY15B128Q-SXAT datasheet, CY15B128Q-SXAT pinout, CY15B128Q-SXAT application, or CY15B128Q-SXAT equivalent, key selection criteria include write-cycle speed vs. serial flash/EEPROM, SPI mode compatibility, hardware/software write protection granularity, and automotive temperature compliance without refresh or wear leveling overhead.

Technical Context

The CY15B128Q-SXAT implements a ferroelectric memory array accessed via standard SPI protocol, eliminating write latency by performing byte-level writes at bus speed - no polling or erase cycles required. Its internal logic includes an 8-bit nonvolatile status register controlling block protection (1/4, 1/2, or full array) and WPEN-enabled hardware write protection.

It operates as a true SPI slave with synchronous I/O: SI latched on rising SCK edge, SO driven on falling edge, and CS-driven transaction framing. The device ID (manufacturer + product ID) is readable via dedicated instruction, enabling host firmware identification without external configuration.

Key Specifications

Pinout & Package

8-pin small outline integrated circuit (SOIC) package with gull-wing leads, RoHS-compliant, 150 mil body width.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25DF041A-SSH-T and M95M02-DRMN6TP/K, CY15B128Q-SXAT uniquely delivers deterministic sub-microsecond writes, 100-trillion-cycle endurance, and automotive-grade reliability - making it the only viable option for real-time, high-frequency nonvolatile logging in safety-critical systems.

Availability

CY15B128Q-SXAT is available at Aetrix Electronics and suitable for automotive telematics, ADAS data buffering, infotainment configuration storage, and body control module parameter retention requiring stable component supply across extended production lifecycles.

Supply support for CY15B128Q-SXAT 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 semiconductor solutions for automotive, industrial, and IoT applications, with emphasis on low-power, nonvolatile memory and programmable system-on-chip architectures.

The CY15B128Q belongs to Cypress's automotive F-RAM product line, engineered specifically to replace serial flash and EEPROM in applications demanding ultra-high endurance, zero-write-latency, and guaranteed data retention under harsh thermal and power conditions.

FAQ

Is CY15B128Q-SXAT pin-compatible with standard 8-pin SOIC SPI flash or EEPROM devices?

Yes - it uses identical 8-pin SOIC footprint and SPI signal mapping (CS, SCK, SI, SO, WP, HOLD, VDD, VSS). No PCB redesign is needed for drop-in replacement of serial flash or EEPROM in existing automotive designs, provided timing and voltage margins align with its 2.0–3.6 V and 40 MHz specs.

Does CY15B128Q-SXAT require special initialization or firmware drivers beyond standard SPI?

No - it uses industry-standard SPI opcodes (e.g., 0x03 for Read, 0x02 for Write, 0x05 for RDSR) and requires only basic SPI master configuration. Firmware changes are limited to removing write-polling loops and adjusting timing margins to exploit its NoDelay™ capability.

How does the HOLD pin function during active memory operations?

HOLD suspends ongoing SPI transactions (read or write) immediately upon going LOW while SCK is LOW. The device retains internal state and resumes from the exact bit position when HOLD returns HIGH - enabling CPU context switching without data loss or transaction restart overhead.

What happens if the WP pin is left floating?

Leaving WP floating violates the datasheet requirement and may cause unintended write protection failure. The pin has a weak internal pull-up, but automotive environments demand deterministic behavior - Cypress specifies WP must be tied to VDD if unused to ensure reliable status register write enablement.