Renesas AT25DF256-XMHN-T

Overview

AT25DF256-XMHN-T from Renesas Electronics is a 256-Kbit serial Flash memory IC with SPI interface, supporting dual-output read mode for enhanced throughput in embedded code and data storage applications. It operates from 1.65 V to 3.6 V, delivers 104 MHz max clock frequency, achieves 6 ns clock-to-output delay, and features flexible erase granularity (256-byte page, 4-kByte/32-kByte blocks, full chip).

For engineers reviewing the AT25DF256-XMHN-T datasheet, AT25DF256-XMHN-T pinout, AT25DF256-XMHN-T application, or AT25DF256-XMHN-T equivalent, key selection considerations include its dual-output read capability, ultra-deep power-down current (200 nA), OTP security register (128 bytes), hardware write protection via WP pin, and JEDEC-standard ID read support.

Technical Context

The AT25DF256-XMHN-T implements a standard SPI master-slave interface compliant with Modes 0 and 3, using rising-edge input sampling and falling-edge output timing. Its internal architecture includes dedicated address latches, I/O buffers, status register logic, and OTP security register with factory-programmed 64-byte unique identifier plus 64-byte user-programmable space.

Device operation relies on opcode-driven command sequences initiated by CS assertion, supporting dual-output read (3Bh) for 2-bit-per-cycle data transfer, byte/page program (02h), and multiple erase commands (81h, 20h, 52h, D8h, 60h/C7h). Protection is enforced via software status bits and hardware WP pin control of sector locking.

Key Specifications

Pinout & Package

AT25DF256-XMHN-T is packaged in an 8-lead TSSOP (4.4 mm body width), pin-compatible with industry-standard SOIC-8 and UDFN-8 footprints. Pin functions are electrically identical across all package variants.

Key Features

Applications

Equivalent & Alternatives

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

Compared with W25Q256JWEIQ and MT25QL256ABA8ESF-0SIT, AT25DF256-XMHN-T offers uniquely optimized 256-Kbit density with dual-output read, ultra-low 200 nA power-down, and integrated OTP security-making it ideal for compact, battery-sensitive, identity-critical embedded systems where minimal footprint and deterministic timing are prioritized over raw bandwidth or capacity.

Availability

AT25DF256-XMHN-T is available at Aetrix Electronics and suitable for embedded boot memory, firmware update storage, and secure device identity applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AT25DF256-XMHN-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

Renesas Electronics is a global semiconductor leader delivering microcontrollers, analog, power, and memory solutions for automotive, industrial, and IoT markets.

The AT25DF256-XMHN-T belongs to Renesas' serial Flash memory product line, designed specifically for cost-sensitive, low-power embedded systems needing reliable code and data storage with hardware-enforced security and flexible erase architecture.

FAQ

What is the maximum operating frequency supported by the AT25DF256-XMHN-T?

The AT25DF256-XMHN-T supports a maximum clock frequency of 104 MHz for most commands including Read Array (0Bh), Page Erase (81h), and Block Erase (20h/52h). This enables high-throughput data access while maintaining compatibility with common SPI peripherals. The AT25DF256-XMHN-T achieves 6 ns clock-to-output delay at this speed, ensuring minimal latency in time-critical read operations.

Does the AT25DF256-XMHN-T support dual-output read mode, and how is it enabled?

Yes, the AT25DF256-XMHN-T supports dual-output read mode using the 3Bh opcode. During this mode, both SI (I/O0) and SO (I/O1) pins function as concurrent data outputs, delivering two bits per clock cycle to double effective read bandwidth. No configuration register setting is required-activation is command-driven, and the device automatically configures I/O0 as output upon receiving the 3Bh command sequence.

What is the purpose and structure of the OTP security register in the AT25DF256-XMHN-T?

The AT25DF256-XMHN-T includes a 128-byte One-Time Programmable (OTP) security register, with 64 bytes factory-programmed with a unique device identifier and 64 bytes user-programmable. It is accessed via 9Bh (program) and 77h (read) commands. Once programmed, OTP bytes cannot be altered, making it suitable for secure device serialization, cryptographic key storage, and ESN binding in regulated applications.

How does hardware write protection work on the AT25DF256-XMHN-T?

Hardware write protection on the AT25DF256-XMHN-T is controlled by the active-low WP pin. When asserted (low), it locks protected memory sectors as defined by status register bits and block protection settings. The WP pin is internally pulled high, so it may be left floating if unused-but Renesas recommends tying it to VCC for noise immunity. Protection remains active even during power transitions, preventing spurious writes.

What power-saving modes does the AT25DF256-XMHN-T offer, and what are their typical current draws?

The AT25DF256-XMHN-T provides three low-power states: Standby (25 µA typical), Deep Power-Down (5 µA typical), and Ultra-Deep Power-Down (200 nA typical). Entry is command-driven (B9h or 79h opcodes), and exit requires specific resume commands (ABh or 79h toggle). These modes enable aggressive energy management in battery-powered AT25DF256-XMHN-T applications such as wireless sensors and portable diagnostics.