Microchip Technology AT25P1024W1-10SI-2.7

Overview

AT25P1024W1-10SI-2.7 from Atmel is a 1 Mbit (131,072 × 8) SPI serial EEPROM optimized for low-voltage industrial applications, operating across 2.7V–5.5V, supporting SPI Modes 0 and 3, and delivering 2.1 MHz clock rate with 128-byte page-write only operation.

For engineers reviewing the AT25P1024W1-10SI-2.7 datasheet, AT25P1024W1-10SI-2.7 pinout, AT25P1024W1-10SI-2.7 application, or AT25P1024W1-10SI-2.7 equivalent, key selection considerations include its 20-lead SOIC package, hardware/software write protection via WP/HOLD pins, self-timed 5 ms typical write cycle, 100,000 endurance cycles, and 40+ year data retention.

Technical Context

The AT25P1024W1-10SI-2.7 implements a synchronous 3-wire SPI slave interface (CS/SCK/SI/SO) with separate input/output data paths and MSB-first transmission. It uses an 8-bit instruction register with op-codes for WREN, WRDI, RDSR, WRSR, READ, and WRITE, and supports HOLD suspension without sequence reset.

Block write protection is controlled nonvolatively via BP1/BP0 bits in the status register to lock 0%, 25%, 50%, or 100% of the memory array; WPEN bit enables/disables hardware protection through the WP pin, and RDY/WEN bits provide real-time status feedback during internal write cycles.

Key Specifications

Pinout & Package

AT25P1024W1-10SI-2.7 is packaged in a 20-lead JEDEC SOIC (20S2) with gull-wing leads, 0.300" body width, 1.27 mm pitch, and 8.00 mm × 5.00 mm footprint. Pin 1 is marked at top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95M01-RDW6TP/K and BR24G1M-3A, the AT25P1024W1-10SI-2.7 provides deterministic SPI Mode 0/3 timing, dual hardware/software write protection via dedicated WP/HOLD pins, and JEDEC SOIC packaging suited for industrial reflow processes-making it optimal for legacy SPI-based control systems requiring robust physical security and suspend capability.

Availability

AT25P1024W1-10SI-2.7 is available at Aetrix Electronics and suitable for industrial sensor calibration storage, medical device configuration memory, and automotive body control module NVM requiring stable component supply, long-life data retention, and industrial temperature compliance.

Supply support for AT25P1024W1-10SI-2.7 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

Atmel Corporation (now part of Microchip Technology) is a semiconductor company specializing in microcontrollers, nonvolatile memory, and security ICs for embedded systems.

The AT25P1024 series was designed as a high-reliability, low-voltage SPI EEPROM family targeting industrial automation, medical instrumentation, and automotive subsystems requiring guaranteed 40+ year data retention and 100,000 write cycles.

FAQ

What is the maximum SPI clock frequency supported by the AT25P1024W1-10SI-2.7?

The AT25P1024W1-10SI-2.7 supports a maximum SCK clock frequency of 2.1 MHz across its full 2.7V–5.5V supply range and -40°C to +85°C operating temperature. This value is specified in the AC Characteristics table under fSCK and applies to both SPI Mode 0 and Mode 3 operation. The device maintains timing compliance without requiring external clock dividers or protocol adaptation.

Does the AT25P1024W1-10SI-2.7 support individual byte writes or only page writes?

The AT25P1024W1-10SI-2.7 supports page writes only-specifically 128-byte aligned writes-and does not support single-byte or sub-page programming. Attempting to write fewer than 128 bytes results in undefined content in that page. This design enforces atomicity and reduces wear leveling complexity, and is explicitly stated in the datasheet's "128-byte Page Mode Only for Write Operations" feature.

How does hardware write protection work on the AT25P1024W1-10SI-2.7?

Hardware write protection on the AT25P1024W1-10SI-2.7 is enabled when the WPEN bit in the status register is set to "1" and the WP pin is driven low. In this state, writes to the status register-including BP0/BP1 and WPEN itself-and to block-protected memory regions are disabled. If WPEN=0, the WP pin has no effect, allowing full register access regardless of WP pin state.

What is the purpose of the HOLD pin on the AT25P1024W1-10SI-2.7?

The HOLD pin on the AT25P1024W1-10SI-2.7 allows the host microcontroller to suspend an ongoing SPI transaction without resetting the internal address counter or losing synchronization. When asserted low (with SCK low), SO goes high-impedance and SI is ignored; resuming requires bringing HOLD high while SCK remains low. This enables deterministic interrupt handling in real-time systems.

Is the AT25P1024W1-10SI-2.7 compatible with standard SPI Mode 0 and Mode 3 interfaces?

Yes, the AT25P1024W1-10SI-2.7 is explicitly compatible with SPI Modes 0 (CPOL=0, CPHA=0) and 3 (CPOL=1, CPHA=1), as confirmed in the Features section and timing diagrams. Its SI sampling and SO output edges align precisely with these modes, enabling plug-and-play integration with common microcontrollers including ARM Cortex-M, PIC, and AVR families without custom bit-banging logic.