Renesas RM25C32DS-LTAI-B

Overview

RM25C32DS-LTAI-B from Adesto Technologies is a 32Kbit serial EEPROM memory IC using CBRAM® resistive technology, operating from 1.65V to 3.6V with SPI interface (modes 0 and 3), 10 MHz fast read capability, and 100,000 write cycles endurance. It serves as non-volatile data storage in space-constrained embedded systems requiring ultra-low power and high reliability.

For engineers reviewing the RM25C32DS-LTAI-B datasheet, RM25C32DS-LTAI-B pinout, RM25C32DS-LTAI-B application, or RM25C32DS-LTAI-B equivalent, key selection criteria include its 0.5 µA ultra-deep power-down current, 60 µs byte-write latency, OTP security register, auto power-down behavior, and compatibility with industrial temperature range (–40°C to +85°C) designs.

Technical Context

The RM25C32DS-LTAI-B implements a 4-wire SPI interface (CS, SCK, SDI, SDO) with HOLD and WP pins for flow control and hardware write protection. Its CBRAM® core enables true byte-level direct-write without pre-erase, eliminating read-modify-write overhead typical of floating-gate EEPROMs.

It features dual-status registers (non-volatile Byte 1 and volatile Byte 2), supports page (32-byte) and byte programming, and integrates configurable low-power modes - including auto Ultra-Deep Power-Down after write completion and programmable Low Power Standby Enable (LPSE) - all managed via SPI commands and status bits.

Key Specifications

Pinout & Package

RM25C32DS-LTAI-B is housed in an 8-lead TSSOP package (3.0 mm × 4.4 mm, 0.65 mm pitch), RoHS-compliant and halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25DF041A-SSH-T and M95M04-DRMN6TP/K, RM25C32DS-LTAI-B delivers superior energy efficiency per write operation, guaranteed endurance across temperature, and integrated security features - making it optimal for compact, battery-operated, or safety-critical parameter storage where reliability and low quiescent power are design priorities.

Availability

RM25C32DS-LTAI-B is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical wearables, automotive body electronics, and IoT sensor node designs requiring stable component supply, long-term lifecycle support, and guaranteed RoHS/halogen-free compliance.

Supply support for RM25C32DS-LTAI-B 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

Adesto Technologies (acquired by Dialog Semiconductor in 2020, now part of Renesas Electronics) specialized in ultra-low-power non-volatile memory solutions based on proprietary resistive switching technologies.

The RM25C32DS-LTAI-B belongs to Adesto's CBRAM®-based serial EEPROM product line, engineered for applications demanding high endurance, minimal energy per write, and robust operation across extended temperature and radiation-exposed environments.

FAQ

What is the maximum clock frequency supported by RM25C32DS-LTAI-B in fast read mode?

The RM25C32DS-LTAI-B supports up to 10 MHz SCK frequency in fast read mode (FREAD command, 0Bh), enabling high-throughput data retrieval while maintaining signal integrity on compact PCB layouts. This is double the 1.6 MHz limit of normal read mode (READ command, 03h) and is validated under CL = 10 pF loading per the DS-RM25C32DS–124C datasheet.

Does RM25C32DS-LTAI-B require pre-erase before byte programming?

No, RM25C32DS-LTAI-B does not require pre-erase before byte programming. As a CBRAM®-based device, it supports true direct-write: any byte can be overwritten in-place without erasing surrounding cells or entire pages. This eliminates the read-modify-write overhead inherent in floating-gate EEPROMs and contributes to its 100,000-cycle endurance guarantee.

How does the OTP Security Register function in RM25C32DS-LTAI-B?

The RM25C32DS-LTAI-B includes a 64-byte One-Time Programmable (OTP) Security Register: the first 32 bytes are factory-programmed with a unique device identifier, and the remaining 32 bytes are user-programmable once. Access is via ROTPSR (77h) and POTPSR (9Bh) commands. This register supports secure boot binding, anti-cloning, and cryptographic key derivation in trusted execution environments.

What power-down modes are available on RM25C32DS-LTAI-B, and how do they differ?

RM25C32DS-LTAI-B offers three low-power states: Standby (CS high, ~77 µA), Power-Down (PD command, ~2.8 µA), and Ultra-Deep Power-Down (UDPD command, 0.04 µA typical). Auto Ultra-Deep Power-Down can be enabled (AUDPD bit) to enter UDPD automatically after write completion. Only the Exit Ultra-Deep Power-Down sequence wakes the device from UDPD - all other commands are ignored.

Is RM25C32DS-LTAI-B compatible with standard SPI controllers?

Yes, RM25C32DS-LTAI-B is fully compatible with standard SPI controllers supporting Mode 0 (CPOL=0, CPHA=0) and Mode 3 (CPOL=1, CPHA=1). It uses standard 4-wire SPI (CS, SCK, SDI, SDO) with optional HOLD and WP pins. All instructions follow JEDEC-standard opcodes (e.g., 03h for READ, 02h for WRITE), and timing meets SPI bus specifications across its 1.65–3.6 V supply range.