Renesas RM25C32C-BSNC-T

Overview

RM25C32C-BSNC-T from Adesto Technologies is a 32Kbit EEPROM-compatible serial non-volatile memory IC based on CBRAM® resistive technology, operating from 2.7V to 3.6V, supporting SPI modes 0 and 3, with 5MHz fast read capability and 32-byte page write in ≤1ms. It serves as low-power, high-endurance firmware/data storage in microcontroller-based edge sensors and IoT endpoint nodes.

For engineers reviewing the RM25C32C-BSNC-T datasheet, RM25C32C-BSNC-T pinout, RM25C32C-BSNC-T application, or RM25C32C-BSNC-T equivalent, key selection criteria include its 25,000 write cycles, 10-year data retention, 5µA power-down current, SOIC-8 package compatibility, and SPI interface timing compliance with JEDEC MS-012 AA.

Technical Context

The RM25C32C-BSNC-T implements a 4-wire SPI interface (CS, SCK, SDI, SDO) with HOLD and WP pins, supports self-timed byte/page write and page/chip erase, and uses internal address latching with automatic rollover during sequential reads. Its CBRAM® core enables 10% energy consumption versus comparable EEPROMs for byte writes.

It features dual read modes-normal (1.6MHz SCK max) and fast (5MHz SCK max with 1 dummy byte), a single 8-bit status register (WIP/WEL bits), and instruction set including WREN, WR, READ, FREAD, PERS, CERS, PD, and RES-all executed MSB-first with CS-controlled framing and no external timing dependencies.

Key Specifications

Pinout & Package

RM25C32C-BSNC-T is housed in an 8-lead JEDEC SOIC (SN) package, 0.150" wide body, compliant with MS-012 Variation AA. Dimensions: D = 4.80–5.05mm, E1 = 3.81–3.99mm, e = 1.27mm pitch. RoHS-compliant and halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25DF041A-SSH-T and M95M04-DRMN6TP/K, RM25C32C-BSNC-T uniquely balances sub-millisecond write latency, ultra-low power-down current, and hardware HOLD functionality - making it optimal for battery-constrained, latency-sensitive embedded systems requiring frequent small-data updates.

Availability

RM25C32C-BSNC-T is available at Aetrix Electronics and suitable for industrial sensor nodes, medical wearables, smart meter firmware vaults, and automotive telematics log buffers requiring stable component supply across multi-year production programs.

Supply support for RM25C32C-BSNC-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) specialized in ultra-low-power non-volatile memory solutions using proprietary CBRAM® technology for IoT and edge applications.

The RM25C32C-BSNC-T belongs to Adesto's Mavriq™ family of CBRAM-based serial memories, designed specifically to replace legacy EEPROMs in space-, power-, and latency-constrained embedded systems without sacrificing reliability.

FAQ

What is the maximum SPI clock frequency supported by RM25C32C-BSNC-T in fast read mode?

The RM25C32C-BSNC-T supports a maximum SCK frequency of 5MHz in fast read mode (FREAD command), requiring a 1-byte dummy cycle after the 2-byte address. This is confirmed in Section 3.2 AC Operating Characteristics of the DS-RM25C32C–063F–1/2018 datasheet, where fSCKF is specified as 0–5MHz. The RM25C32C-BSNC-T achieves this timing with CL = 10pF and tOV ≤6.5ns.

Does RM25C32C-BSNC-T require external pull-up resistors on its SPI lines?

RM25C32C-BSNC-T does not require external pull-ups on SDO, as it is actively driven or tri-stated. However, CS, SCK, SDI, HOLD, and WP lines should be pulled up (typically 10kΩ) to VCC when unused or shared on multi-drop buses to prevent floating inputs that could trigger spurious commands. This is implied by the VIH/VIL specifications (VCC × 0.7 / VCC × 0.3) and absolute maximum ratings.

How many write cycles can RM25C32C-BSNC-T endure before failure?

The RM25C32C-BSNC-T is rated for 25,000 write cycles per memory location, validated per JEDEC JESD22-A117B. This endurance applies to both byte and page writes and is guaranteed across the commercial temperature range (0°C to +70°C). The RM25C32C-BSNC-T retains data for 10 years at 70°C after the final write, as stated in Section 3.2 and the Features list.

Is RM25C32C-BSNC-T pin-compatible with standard SOIC-8 EEPROMs like the AT25040?

No - RM25C32C-BSNC-T uses the same 8-lead SOIC (SN) mechanical footprint as AT25040, but pin functions differ: RM25C32C-BSNC-T assigns Pin 3 to WP and Pin 7 to HOLD, whereas AT25040 uses Pin 3 for NC and Pin 7 for HOLD only in certain variants. Direct replacement requires PCB layout verification and firmware adaptation for HOLD/WP handling and CBRAM-specific timing.

What happens to RM25C32C-BSNC-T during power-up, and how long before it accepts commands?

Upon VCC ramp-up, RM25C32C-BSNC-T enters reset until tPUD (75µs minimum) elapses, after which it becomes fully accessible. During this period, all commands are rejected. The RM25C32C-BSNC-T powers up with WEL = 0, so a WREN instruction must precede any write/erase operation. This behavior is defined in Figure 4-3 (Power-up Timing) and Section 3.1 DC Operating Characteristics.