Renesas AT45DB081D-SU-2.5-AD

Overview

AT45DB081D-SU-2.5-AD from Adesto Technologies is an 8-Mbit serial DataFlash memory IC with RapidS™ SPI-compatible interface, 256/264-byte page architecture, dual 256-/264-byte SRAM buffers, and industrial temperature support. It delivers up to 66 MHz read speed, 100,000 program/erase cycles per page, and 20-year data retention for embedded code shadowing and firmware storage.

For engineers reviewing the AT45DB081D-SU-2.5-AD datasheet, AT45DB081D-SU-2.5-AD pinout, AT45DB081D-SU-2.5-AD application, or AT45DB081D-SU-2.5-AD equivalent, key selection criteria include page-size configurability (256 vs. 264 bytes), buffer-assisted concurrent read/write capability, hardware write protection via WP pin, and sector lockdown for secure boot code storage.

Technical Context

The AT45DB081D-SU-2.5-AD implements a sequential-access Flash architecture with two independent 256-/264-byte SRAM buffers enabling simultaneous data reception and main memory reprogramming. Its RapidS interface supports SPI Modes 0 and 3 at up to 66 MHz, with continuous array read bypassing buffers to enable seamless code shadowing across page boundaries.

Memory organization comprises 4,096 pages (256 or 264 bytes each), grouped into 16 sectors (sector 0 split into 0a/0b), with flexible erase granularity: page (256 B), block (2 KB), sector (64 KB), or chip (8 Mbit). All program/erase operations are self-timed and require no external high-voltage supply.

Key Specifications

Pinout & Package

AT45DB081D-SU-2.5-AD is packaged in an 8-pin SOIC (Small Outline Integrated Circuit) with standard 150-mil body width and RoHS-compliant green finish.

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-SU-2.5-AD uniquely combines dual SRAM buffers for true concurrent I/O, hardware-enforced sector lockdown, and factory-configurable page size - making it optimal for secure, high-reliability embedded systems requiring robust OTA update infrastructure.

Availability

AT45DB081D-SU-2.5-AD is available at Aetrix Electronics and suitable for industrial HMI firmware storage, medical device bootloader protection, and smart meter firmware updates requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for AT45DB081D-SU-2.5-AD 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 low-power, high-reliability nonvolatile memory and analog interface solutions for IoT and industrial edge devices.

The AT45DB081D-SU-2.5-AD belongs to the DataFlash® family, designed specifically for embedded systems needing efficient code shadowing, secure firmware storage, and seamless in-system reprogrammability without high-voltage programming circuits.

FAQ

What is the maximum clock frequency supported by AT45DB081D-SU-2.5-AD for continuous array read operations?

The AT45DB081D-SU-2.5-AD supports up to 66 MHz for Continuous Array Read using opcodes 0BH (High Frequency Mode) and E8H (Legacy Command), compliant with SPI Modes 0 and 3. This performance is achievable under valid 2.5 V or 2.7–3.6 V supply conditions and within the industrial temperature range. The fCAR1 specification defines this limit, and timing must adhere to the datasheet's detailed bit-level read timing diagrams.

Does AT45DB081D-SU-2.5-AD support both 256-byte and 264-byte page sizes, and how is the selection made?

Yes, AT45DB081D-SU-2.5-AD supports user-configurable page sizes of either 256 bytes (power-of-2 binary format) or 264 bytes (DataFlash standard format). The selection is determined at power-up by reading the status register's PSZ bit; factory pre-configuration for 256-byte pages is also possible. Addressing differs: 256-byte mode uses A19–A0 addressing, while 264-byte mode uses PA11–PA0 and BA8–BA0 for page and byte offsets.

How does the dual-buffer architecture of AT45DB081D-SU-2.5-AD improve system-level throughput?

The AT45DB081D-SU-2.5-AD integrates two independent 256-/264-byte SRAM buffers that operate asynchronously from the main Flash array. This allows the host to load new data into one buffer while the other buffer's contents are being programmed into Flash - eliminating idle time during page writes and enabling continuous data streaming. This concurrency directly reduces effective firmware update latency in resource-constrained microcontroller systems.

What hardware security mechanisms does AT45DB081D-SU-2.5-AD provide for protecting critical firmware sections?

AT45DB081D-SU-2.5-AD provides three hardware security layers: (1) a dedicated WP pin that overrides all software protection when asserted low, (2) sector lockdown that permanently disables program/erase on selected sectors, and (3) a 128-byte security register containing 64 bytes of user-programmable space and a unique 64-byte device identifier. These features collectively prevent unauthorized modification of bootloader or calibration data without physical access and deliberate unlock procedures.

Is AT45DB081D-SU-2.5-AD compatible with standard SPI controllers, and what modes does it support?

Yes, AT45DB081D-SU-2.5-AD is fully compatible with standard SPI controllers and supports SPI Modes 0 (CPOL = 0, CPHA = 0) and 3 (CPOL = 1, CPHA = 1). Data is sampled on the rising edge of SCK for SI and shifted out on the falling edge for SO. No special controller extensions are required - standard SPI peripheral initialization with appropriate clock polarity and phase settings suffices for full command set execution.