Renesas RM24C32DS-LSNI-T

Overview

RM24C32DS-LSNI-T from Adesto Technologies is a 32-Kbit serial EEPROM IC using CBRAM® resistive memory technology, operating from 1.65V to 3.6V with I²C interface up to 1 MHz, 32-byte page size, and 128-byte OTP security register. It delivers ultra-low-energy byte writes (50 nJ), 100,000 write cycles, and >40-year data retention at 125°C for secure firmware storage in space-constrained industrial sensors.

For engineers reviewing the RM24C32DS-LSNI-T datasheet, RM24C32DS-LSNI-T pinout, RM24C32DS-LSNI-T application, or RM24C32DS-LSNI-T equivalent, key selection criteria include I²C speed compatibility (100 kHz/400 kHz/1 MHz), WP-controlled hardware write protection, E0–E2 addressable multi-device bus topology, and OTP register partitioning (64B factory ID + 64B user-programmable).

Technical Context

The RM24C32DS-LSNI-T implements a slave-only 2-wire I²C interface with SDA open-drain and SCL input-only operation, supporting standard, fast, and high-speed modes. Its internal architecture includes a 32-byte page buffer, shared address pointer for EEPROM and OTP registers, and voltage-level sampled WP pin that inhibits writes only upon STOP command assertion.

CBRAM® technology enables true byte-level write endurance without read-modify-write overhead-unlike floating-gate EEPROMs-delivering consistent 100,000-cycle endurance across -40°C to +85°C and eliminating degradation between byte and page write modes. The device uses direct-write physics, so each byte is written independently regardless of access pattern.

Key Specifications

Pinout & Package

RM24C32DS-LSNI-T is packaged in an 8-lead SOIC (Small Outline Integrated Circuit) with standard JEDEC MS-012AC footprint (5.3 mm × 4.4 mm, 1.27 mm pitch). Pin 1 is marked with a dot or notch; pin numbering follows counter-clockwise convention from top-left corner when viewed from top.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C32D-SSHM-T and FM24V02A-G, RM24C32DS-LSNI-T uniquely combines high-density (32 Kbit), CBRAM-based endurance (100K cycles across temp), integrated OTP security register, and 3-bit hardware addressing - making it the only option for secure, scalable, thermally robust configuration storage in industrial and automotive edge nodes.

Availability

RM24C32DS-LSNI-T is available at Aetrix Electronics and suitable for industrial sensor calibration, secure firmware storage, IoT edge node identity, and automotive subsystem logging requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for RM24C32DS-LSNI-T 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, high-reliability non-volatile memory solutions for industrial and IoT applications.

The RM24C32DS product line was designed to replace legacy EEPROMs in mission-critical embedded systems demanding higher endurance, lower energy per write, and integrated security - specifically targeting space-constrained, thermally aggressive environments.

FAQ

What is the primary memory technology used in RM24C32DS-LSNI-T?

The RM24C32DS-LSNI-T uses Adesto's proprietary CBRAM® (Conductive Bridging RAM) resistive memory technology. Unlike floating-gate EEPROMs, CBRAM enables true byte-level writes without read-modify-write overhead. This gives RM24C32DS-LSNI-T its 100,000-cycle endurance across temperature, 50 nJ byte write energy, and immunity to endurance degradation between byte and page operations - all confirmed in the DS-RM24C32DS–117B datasheet.

How does the WP pin function on RM24C32DS-LSNI-T?

The WP (Write Protect) pin on RM24C32DS-LSNI-T is active-high: when tied to VCC, it inhibits all write operations (EEPROM array and OTP Security Register), while permitting unrestricted reads. The pin is sampled only at the STOP command edge of each write transaction - toggling WP mid-cycle has no effect. This hardware-level protection ensures RM24C32DS-LSNI-T remains tamper-resistant even if firmware is compromised.

Can RM24C32DS-LSNI-T operate at 1.65V and still achieve 1 MHz I²C speed?

Yes - the RM24C32DS-LSNI-T is fully specified for 1 MHz I²C operation across its entire 1.65V–3.6V supply range, as confirmed in Section 13.3 (AC Characteristics) of the datasheet. At 1.65V, tSCLH/tSCLL minimums remain 500 ns, and fCLK max is maintained at 1 MHz. This enables reliable high-speed communication in ultra-low-voltage battery or energy-harvesting systems without performance trade-offs.

What is the purpose of the E0, E1, and E2 pins on RM24C32DS-LSNI-T?

The E0, E1, and E2 pins on RM24C32DS-LSNI-T form a 3-bit hardware address for I²C multi-drop bus configuration. They are compared against the corresponding bits in the I²C control byte (1010b + E2:E1:E0) to select individual devices. This allows up to eight RM24C32DS-LSNI-T units to share one I²C bus without software address conflicts - essential for modular sensor arrays or stacked PCB designs.

Does RM24C32DS-LSNI-T support both EEPROM and OTP Security Register access over the same I²C interface?

Yes - RM24C32DS-LSNI-T uses the same I²C interface for both memory regions, differentiated only by control byte: "1010" for EEPROM access and "1011" for OTP Security Register access. Both share the same SDA/SCL lines and internal address pointer, but OTP reads/writes mask upper address bits and restrict access to addresses 0–127. This unified interface simplifies driver development while maintaining strict logical separation between general storage and secure identity data.