Renesas AT45DB081D-MU-SL955

Overview

AT45DB081D-MU-SL955 from Adesto Technologies is an 8 Mbit serial DataFlash memory IC with RapidS™ SPI-compatible interface, supporting up to 66 MHz clock frequency, 4,096 pages (256/264-byte configurable), dual 256-/264-byte SRAM buffers, and industrial temperature operation. It serves as nonvolatile storage for firmware code shadowing, voice/image data logging, and embedded program/data retention in space-constrained systems.

For engineers reviewing the AT45DB081D-MU-SL955 datasheet, AT45DB081D-MU-SL955 pinout, AT45DB081D-MU-SL955 application, or AT45DB081D-MU-SL955 equivalent, key selection considerations include page-size configurability (256 vs. 264 bytes), continuous array read capability, hardware write protection via WP pin, sector lockdown security, and 100,000 program/erase cycles per page.

Technical Context

The AT45DB081D-MU-SL955 implements a sequential-access Flash architecture with two independent SRAM buffers enabling simultaneous data reception and Flash reprogramming. Its RapidS interface supports SPI Modes 0 and 3 at up to 66 MHz, with three distinct read commands (03H, 0BH, E8H) optimized for low-, high-, and legacy-frequency operation.

Memory organization includes 16 sectors (0a–15), each containing multiple 2-Kbyte blocks and 256-/264-byte pages. Erase granularity spans page (256 B), block (2 Kbytes), sector (64 Kbytes), and chip (8 Mbits), with all operations self-timed and status-register monitored. Page programming requires either built-in erase (83H/86H) or pre-erased target (88H/89H).

Key Specifications

Pinout & Package

AT45DB081D-MU-SL955 is packaged in an 8-pin MLF (VDFN) with exposed thermal pad (floating or GND-connected), compliant with RoHS, Pb-free, and halide-free requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with W25Q80DVSSIG and MX25L8006EM1I-12G, the AT45DB081D-MU-SL955 uniquely delivers concurrent buffer-to-Flash programming, continuous array read with automatic wraparound, and integrated hardware security - making it optimal for real-time embedded systems requiring both performance and trust.

Availability

AT45DB081D-MU-SL955 is available at Aetrix Electronics and suitable for firmware code shadowing, voice/image data logging, and secure bootloader storage requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AT45DB081D-MU-SL955 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 (now part of Dialog Semiconductor, Renesas Electronics) specialized in low-power, high-reliability serial Flash and nonvolatile memory solutions for industrial and IoT applications.

The AT45DB081D-MU-SL955 belongs to the DataFlash® family, designed specifically for embedded systems needing efficient sequential access, embedded buffering, and robust security - targeting code execution, secure storage, and high-cycle data logging.

FAQ

What is the maximum operating clock frequency for AT45DB081D-MU-SL955?

The AT45DB081D-MU-SL955 supports a maximum RapidS™ serial interface clock frequency of 66 MHz for Continuous Array Read (0BH/E8H) and Main Memory Page Read (D2H) commands. This enables sustained read throughput exceeding 8 MB/s. The actual achievable speed depends on host controller timing margins and PCB layout integrity, but the device guarantees compliance with fCAR1 (66 MHz) and fSCK (50 MHz) specifications per its datasheet.

Does AT45DB081D-MU-SL955 support true byte-level writes like EEPROM?

The AT45DB081D-MU-SL955 does not support direct byte-level writes to Flash, but provides EEPROM emulation through a self-contained three-step read-modify-write operation using its dual SRAM buffers. This allows bit- or byte-alterable behavior in software - for example, updating a single configuration register without erasing an entire 256-byte page. The process is fully managed internally and requires no external buffering logic.

How is page size configured on AT45DB081D-MU-SL955?

Page size on the AT45DB081D-MU-SL955 is factory-configured at wafer test and cannot be changed in-system. It ships either as 256-byte "power-of-2" mode (for EEPROM emulation compatibility) or 264-byte "DataFlash standard" mode (for optimized throughput). The selected mode determines address mapping: 256-byte uses A19–A0 addressing; 264-byte uses PA11–PA0 + BA8–BA0. Datasheet tables and opcodes differ accordingly.

What happens if the WP pin is asserted during a Chip Erase command?

If the WP pin is asserted (low) during Chip Erase initiation, the AT45DB081D-MU-SL955 ignores the C7H/94H/80H/9AH command sequence and remains idle. Chip Erase only proceeds when WP is deasserted (high) at command completion. However, sectors previously locked down or protected via the Sector Protection Register remain unaffected even after successful Chip Erase - their contents persist unless explicitly unlocked first.

Is AT45DB081D-MU-SL955 pin-compatible with earlier AT45DB081B or AT45DB081C variants?

No, AT45DB081D-MU-SL955 is not pin-compatible with AT45DB081B or AT45DB081C. While all share the same 8-pin MLF package outline, the AT45DB081D introduces functional enhancements including deeper power-down mode (15 µA), improved security register structure, and updated command set timing. Migration requires validation of RESET behavior, WP pin interaction, and status register polling sequences per the 3596P–DFLASH–2/2014 datasheet.