Renesas AT25SF081-SSHF-B

Overview

AT25SF081-SSHF-B from Dialog Semiconductor is an 8-Mbit serial flash memory IC supporting SPI Modes 0/3, Dual-I/O and Quad-I/O read operations, with 104 MHz max clock frequency, 6 ns clock-to-output delay, and uniform 4/32/64-Kbyte block erase. It operates from 2.3V–3.6V and targets code shadowing and embedded data storage in consumer electronics.

For engineers reviewing the AT25SF081-SSHF-B datasheet, AT25SF081-SSHF-B pinout, AT25SF081-SSHF-B application, or AT25SF081-SSHF-B equivalent, key selection considerations include SPI interface flexibility (Dual/Quad I/O), industrial temperature range (−40°C to +85°C), hardware write protection via WP pin, security register pages for device serialization, and deep power-down current of 2 µA.

Technical Context

The AT25SF081-SSHF-B implements a flexible erase architecture with four granular erase levels-uniform 4-Kbyte, 32-Kbyte, 64-Kbyte blocks and full chip erase-enabling efficient co-location of code and data without wasted space. Its memory array is organized as 1 Mbyte (0x000000–0xFFFFF) with byte-addressable access and automatic address wraparound.

It supports standard SPI command set including Read Array (03h/0Bh), Dual-Output Read (3Bh), Dual-I/O Read (BBh), Quad-Output Read (6Bh), and Quad-I/O Read (EBh), all requiring QE bit enablement for quad modes. The device integrates three programmable, individually lockable security register pages for ESN, key storage, or serialization.

Key Specifications

Pinout & Package

AT25SF081-SSHF-B uses an 8-lead SOIC (208-mil) package with gull-wing leads, RoHS-compliant and halide-free. Pin functions are validated per DS-25SF081–045K–06/2023.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25SF081-SSHF-B, W25Q80DVSSIG offers lower cost but omits security and high-speed I/O, while MT25QL08GAByx1 delivers higher speed and OTP but lacks lockable security pages-making AT25SF081-SSHF-B uniquely balanced for secure, mixed-code-and-data embedded applications.

Availability

AT25SF081-SSHF-B is available at Aetrix Electronics and suitable for smart home hubs, industrial PLCs, wearable data loggers, and automotive infotainment systems requiring stable component supply and long-term lifecycle support.

Supply support for AT25SF081-SSHF-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

Dialog Semiconductor, acquired Adesto Technologies in 2021, specializes in low-power ICs for IoT, mobile, and industrial applications, with strong focus on energy efficiency and system integration.

The AT25SF081 product line was developed by Adesto (now Dialog) to address code+data co-storage needs in battery-powered and space-constrained embedded systems-emphasizing erase flexibility, security, and SPI interface scalability.

FAQ

What is the operating voltage range of the AT25SF081-SSHF-B?

The AT25SF081-SSHF-B operates from 2.3 V to 3.6 V, making it compatible with both 2.5 V and 3.3 V logic systems without external level shifters. This wide supply range supports designs with varying power rail tolerances and simplifies integration into mixed-voltage platforms. The AT25SF081-SSHF-B maintains full functionality-including Quad-I/O read and security register access-across this entire voltage window.

Does the AT25SF081-SSHF-B support Quad-I/O read, and what is required to enable it?

Yes, the AT25SF081-SSHF-B supports Quad-I/O read using opcode EBh, but requires the Quad Enable (QE) bit in Status Register Byte 2 to be set first. This is done via Write Status Register command (01h) after issuing Write Enable (06h). Once enabled, the SI, SO, WP, and HOLD pins function as I/O0–I/O3 for simultaneous 4-bit data transfer. The AT25SF081-SSHF-B achieves up to 416 Mbps effective throughput in this mode.

How many security register pages does the AT25SF081-SSHF-B have, and can they be locked independently?

The AT25SF081-SSHF-B includes three dedicated security register pages, each 256 bytes in size, designed for secure storage of electronic serial numbers, cryptographic keys, or calibration data. Each page can be individually locked using dedicated lock bits in the status register, preventing overwrite or readback once secured. This capability is intrinsic to the AT25SF081-SSHF-B and requires no external components or firmware overhead to enforce.

What erase block sizes are supported by the AT25SF081-SSHF-B?

The AT25SF081-SSHF-B supports four uniform erase granularities: 4-Kbyte, 32-Kbyte, and 64-Kbyte blocks, plus full-chip erase. These sizes are optimized to align with typical firmware module boundaries and data segment allocations, minimizing wasted space during partial updates. Unlike legacy flash devices with fixed large blocks, the AT25SF081-SSHF-B's flexible architecture allows precise, non-disruptive erasure-critical for reliable OTA updates and runtime data logging.

Is the AT25SF081-SSHF-B suitable for industrial temperature applications?

Yes, the AT25SF081-SSHF-B is specified for the full industrial temperature range of −40°C to +85°C and qualified per JEDEC standards. It maintains guaranteed timing (e.g., 6 ns tV), endurance (100,000 cycles), and data retention (20 years) across this range. The AT25SF081-SSHF-B is commonly deployed in factory automation controllers, outdoor smart meters, and industrial gateways where thermal stability and long-term reliability are mandatory.