Renesas AT25SF161B-SHD-B

Overview

AT25SF161B-SHD-B from Renesas Electronics is a 16-Mbit SPI serial flash memory IC supporting dual I/O and quad I/O operations, with 108 MHz max clock frequency, 2.5–3.6 V supply range, and execute-in-place (XiP) capability for embedded boot and code storage applications.

For engineers reviewing the AT25SF161B-SHD-B datasheet, AT25SF161B-SHD-B pinout, AT25SF161B-SHD-B application, or AT25SF161B-SHD-B equivalent, key selection criteria include quad-SPI timing compliance (1-4-4/0-4-4), 4 kB/32 kB/64 kB erase granularity, OTP security registers, SFDP support, and low-power deep power-down mode (1.5 µA).

Technical Context

The AT25SF161B-SHD-B implements a flexible SPI interface compliant with modes 0 and 3, enabling dual-output (1-1-2), dual-I/O (1-2-2), quad-output (1-1-4), and quad-I/O (1-4-4, 0-4-4) read protocols. Its XiP-optimized architecture supports continuous read with wrap (8/16/32/64-byte) and fast read up to 108 MHz.

Internally, it features three status registers (SR1–SR3), programmable protection via WP pin and non-volatile bits, 3 × 256-byte OTP security registers, and erasable memory blocks sized at 4 kB, 32 kB, and 64 kB - plus full-chip erase - all with verified typical times of 50 ms, 120 ms, 200 ms, and 5.5 s respectively.

Key Specifications

Pinout & Package

AT25SF161B-SHD-B is packaged in an 8-lead SOIC (0.208" wide), with pins arranged top-view counterclockwise from notch: Pin 1 = CS, Pin 2 = SO (I/O1), Pin 3 = WP (I/O2), Pin 4 = GND, Pin 5 = VCC, Pin 6 = HOLD (I/O3), Pin 7 = SCK, Pin 8 = SI (I/O0).

Key Features

Applications

Equivalent & Alternatives

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

Compared with W25Q16JW-QA and MT25QL128ABA1EW9-0SIT, the AT25SF161B-SHD-B delivers optimal balance of XiP-optimized quad-I/O performance, industrial temperature range, integrated OTP security, and low-power deep power-down - making it ideal for cost-sensitive, security-aware embedded systems where 16 Mbit capacity suffices.

Availability

AT25SF161B-SHD-B is available at Aetrix Electronics and suitable for industrial PLC firmware storage, automotive infotainment boot memory, and edge gateway configuration storage requiring stable component supply and long-term lifecycle assurance.

Supply support for AT25SF161B-SHD-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

Renesas Electronics is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for industrial, automotive, and enterprise applications.

The AT25SF161B belongs to Renesas' AT25SF family of SPI flash devices engineered for high-reliability embedded systems requiring execute-in-place, low-power operation, and hardware-based security features.

FAQ

What is the maximum SPI clock frequency supported by the AT25SF161B-SHD-B?

The AT25SF161B-SHD-B supports a maximum SPI clock frequency of 108 MHz in quad-I/O (1-4-4 and 0-4-4) modes. This enables high-throughput read operations critical for execute-in-place (XiP) applications. The device maintains full functionality across its specified 2.5–3.6 V supply range and –40 °C to +85 °C operating temperature, with timing validated per AC characteristics in the official Renesas datasheet DS-AT25SF161B-188 Rev. H.

Does the AT25SF161B-SHD-B support execute-in-place (XiP) operation?

Yes, the AT25SF161B-SHD-B is explicitly designed for execute-in-place operation. It achieves this through quad-SPI support (1-4-4/0-4-4), continuous read mode with wrap, and 108 MHz maximum clock frequency - all documented in the Product Overview section of the Renesas datasheet. These features minimize instruction fetch latency and eliminate the need to copy code into RAM before execution, reducing system memory requirements.

How many one-time programmable (OTP) security registers does the AT25SF161B-SHD-B include?

The AT25SF161B-SHD-B includes three 256-byte one-time programmable (OTP) security registers, totaling 768 bytes of tamper-resistant storage. These registers are accessible via dedicated commands (42h program, 48h read, 44h erase) and are intended for storing cryptographic keys, device identifiers, or secure boot parameters. Their OTP nature ensures irreversible programming, meeting foundational requirements for secure firmware deployment.

What package type is used for the AT25SF161B-SHD-B variant?

The AT25SF161B-SHD-B uses an 8-lead, 0.208" wide EIAJ SOIC package, as confirmed by Renesas' Ordering Information section (page 58 of DS-AT25SF161B-188 Rev. H). This package is RoHS-compliant, halide-free, and Pb-free, and features standard SOIC pinout with exposed pad not present - distinguishing it from DFN or WLCSP variants in the same family.

Does the AT25SF161B-SHD-B support Serial Flash Discoverable Parameters (SFDP)?

Yes, the AT25SF161B-SHD-B implements the Serial Flash Discoverable Parameters (SFDP) register, accessible via command 5Ah. This standardized mechanism allows host systems to automatically detect and configure device parameters - including timing, voltage, and command sets - without requiring hardcoded driver assumptions. SFDP support simplifies software portability and reduces qualification effort across multiple platforms.