Microchip Technology AT45DB011-SI

Overview

AT45DB011-SI from Microchip Technology is a 1-Mbit serial DataFlash memory IC operating from a single 2.7V–3.6V supply, organized as 512 pages × 264 bytes with one 264-byte SRAM buffer, supporting SPI Modes 0 and 3, and used for in-system reprogrammable data storage in industrial embedded systems.

For engineers reviewing the AT45DB011-SI datasheet, AT45DB011-SI pinout, AT45DB011-SI application, or AT45DB011-SI equivalent, this page delivers verified technical context, real-world timing behavior (7 ms page program, 120 µs page-to-buffer transfer), hardware write protection via WP pin, RDY/BUSY signaling, and industrial-temperature (-40°C to +85°C) operation - all critical for reliable firmware/data logging designs.

Technical Context

The AT45DB011-SI implements a serial Flash architecture with dual-level memory hierarchy: main array (512 × 264 B) and dedicated 264-byte SRAM buffer, enabling page-at-a-time programming without external erase cycles. Its command set includes buffer-managed operations (e.g., 53H page-to-buffer transfer, 83H buffer-to-page program with built-in erase).

It uses SPI-compatible three-wire interface (CS/SCK/SI/SO) with hardware flow control via open-drain RDY/BUSY pin and optional page-level write protection via active-low WP pin. Internal self-timed timers manage all erase/program operations, eliminating need for external timing control.

Key Specifications

Pinout & Package

AT45DB011-SI is packaged in a 14-lead TSSOP (14X) with 0.170" width, footprint compatible with JEDEC MO-153, suitable for high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT45DB011-SI, AT45DB011B-SI offers improved process yield and long-term supply assurance while maintaining full electrical and functional equivalence; W25Q80DVSSIG provides greater capacity and speed but sacrifices the integrated SRAM buffer and simplified page-managed command model essential to AT45DB011-SI's use cases.

Availability

AT45DB011-SI is available at Aetrix Electronics and suitable for industrial control systems, embedded data loggers, and medical device firmware storage requiring stable component supply across extended product lifecycles.

Supply support for AT45DB011-SI 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

Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and nonvolatile memory solutions for industrial, automotive, and consumer markets.

The AT45DB011-SI belongs to Microchip's DataFlash family - designed specifically for systems needing simple, reliable, low-pin-count serial Flash with integrated buffer management to replace parallel NOR/NAND or EEPROM in resource-constrained embedded applications.

FAQ

What is the maximum clock frequency supported by the AT45DB011-SI?

The AT45DB011-SI supports a maximum SCK frequency of 13 MHz, as specified in its AC characteristics table. This timing enables efficient data transfer during read, write, and status polling operations. The device maintains signal integrity and timing compliance across its full industrial temperature range (-40°C to +85°C), and operation above 13 MHz is not guaranteed and may result in command failures or data corruption. Always observe setup/hold times (e.g., tSU = 10 ns, tH = 20 ns) when interfacing with host controllers.

Does the AT45DB011-SI require a high-voltage programming supply?

No, the AT45DB011-SI does not require a high-voltage programming supply. It operates entirely from a single 2.7V–3.6V supply for both read and program/erase functions. All internal voltage boosting is handled on-chip, eliminating the need for external charge pumps or 12V rails. This simplifies power design and enhances system safety - a key advantage over traditional parallel Flash devices. The AT45DB011-SI achieves this using proprietary internal circuitry that generates necessary programming voltages from VCC.

How does the hardware write protection (WP pin) function on the AT45DB011-SI?

When the WP pin on the AT45DB011-SI is driven low, it permanently disables programming and erasure of the first 256 pages (pages 0–255) of main memory. Pages 256–511 remain fully writable. The WP pin is internally pulled high, so leaving it unconnected defaults to unprotected mode. For robust protection, Microchip recommends externally driving WP high via a pull-up resistor - especially in noisy industrial environments where floating pins could cause unintended lock/unlock behavior.

Can the AT45DB011-SI be used in SPI Mode 0 or only Mode 3?

The AT45DB011-SI is explicitly compatible with both SPI Mode 0 (CPOL = 0, CPHA = 0) and SPI Mode 3 (CPOL = 1, CPHA = 0), as confirmed in its datasheet features and timing diagrams. The device automatically detects the inactive clock polarity on each falling edge of CS and adapts accordingly. This dual-mode support allows seamless integration with diverse host MCUs - whether legacy 8-bit controllers using Mode 0 or modern ARM-based SoCs defaulting to Mode 3 - without hardware or firmware changes.

What is the purpose of the 264-byte SRAM buffer in the AT45DB011-SI?

The 264-byte SRAM buffer in the AT45DB011-SI serves as an intermediate staging area for data manipulation prior to committing to Flash. It enables critical operations like Main Memory Page to Buffer Transfer (53H), Buffer Write (84H), and Auto Page Rewrite (58H), allowing atomic read-modify-write sequences without host RAM involvement. This buffer eliminates the need for external memory in space-constrained designs and ensures data integrity during partial-page updates - a core architectural advantage distinguishing AT45DB011-SI from standard SPI Flash devices.