Microchip Technology AT25640AY1-10YI-2.7

Overview

AT25640AY1-10YI-2.7 from Microchip Technology (formerly Atmel) is a 64 Kbit SPI serial EEPROM organized as 8192 × 8-bit memory, supporting 2.7–5.5 V operation, 20 MHz clock rate at 5 V, 32-byte page write, and automotive-grade extended temperature (−40°C to +85°C). It delivers high-reliability nonvolatile storage for firmware parameter retention in engine control units.

For engineers reviewing the AT25640AY1-10YI-2.7 datasheet, AT25640AY1-10YI-2.7 pinout, AT25640AY1-10YI-2.7 application, or AT25640AY1-10YI-2.7 equivalent, key selection criteria include its 8-lead MAP package footprint, hardware/software write protection via WP pin and status register, HOLD pin for interruptible serial communication, and guaranteed 1 million write cycles with 100-year data retention.

Technical Context

The AT25640AY1-10YI-2.7 operates as an SPI slave device with fixed 3-wire interface (CS, SCK, SI/SO), supports SPI modes 0 and 3, and uses MSB-first transmission. Its internal architecture includes an 8-bit instruction register handling WREN/WRDI/RDSR/WRSR/READ/WRITE op-codes and a status register with nonvolatile BP0/BP1/WPEN bits for block protection configuration.

Write operations require explicit WREN instruction prior to WRITE; self-timed internal write cycle completes in ≤5 ms. The HOLD pin suspends ongoing serial transfers without resetting sequence state, while WP pin-when enabled via WPEN bit-blocks status register writes during low assertion, providing dual-layer data integrity for safety-critical systems.

Key Specifications

Pinout & Package

AT25640AY1-10YI-2.7 uses an 8-lead Miniature Array Package (MAP), 4.90 mm × 3.00 mm body, non-leaded, dual footprint compatible with SOIC and TSSOP layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95640-DW and 25AA640A-I/MS, AT25640AY1-10YI-2.7 uniquely combines automotive-grade temperature range, HOLD pin support, and 20 MHz performance in the compact 8Y1 MAP package-making it optimal for space-constrained, safety-aware automotive and industrial control nodes.

Availability

AT25640AY1-10YI-2.7 is available at Aetrix Electronics and suitable for engine control units, industrial PLCs, medical infusion pumps, and smart energy meters requiring stable component supply across extended product lifecycles.

Supply support for AT25640AY1-10YI-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

Microchip Technology is a global semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with broad industrial and automotive qualifications.

AT25640AY1-10YI-2.7 belongs to Microchip's legacy Atmel SPI EEPROM product line, designed specifically for robust, low-power, nonvolatile data storage in safety-critical automotive and industrial control systems.

FAQ

What is the maximum clock frequency supported by AT25640AY1-10YI-2.7?

AT25640AY1-10YI-2.7 supports up to 20 MHz SCK frequency at VCC = 5.0 V. At lower voltages (2.7–3.6 V), the maximum clock rate is reduced to 10 MHz per AC characteristics tables. This ensures reliable timing margin across its full 2.7–5.5 V operating range, and the device automatically adapts to the applied VCC without configuration.

Does AT25640AY1-10YI-2.7 include hardware write protection independent of software control?

Yes, AT25640AY1-10YI-2.7 provides independent hardware write protection via the WP pin. When the WPEN bit in the status register is set to "1", pulling WP low disables all writes to the status register-including BP0/BP1 and WPEN itself-regardless of WREN state. This creates a physical lock that cannot be overridden by firmware, essential for protecting bootloader configuration in certified systems.

What package type is used for AT25640AY1-10YI-2.7 and what are its key mechanical features?

AT25640AY1-10YI-2.7 uses the 8Y1 Miniature Array Package (MAP): 4.90 mm × 3.00 mm body, 0.65 mm pitch, non-leaded, dual footprint compatible with JEDEC SOIC and TSSOP land patterns. Its compact size and low profile (max 0.90 mm height) enable high-density placement in automotive modules and portable medical devices where board space is constrained.

How does the HOLD pin function during an active SPI transaction on AT25640AY1-10YI-2.7?

The HOLD pin on AT25640AY1-10YI-2.7 pauses serial communication without resetting the internal address counter or command state. When asserted low while SCK is low, SO enters high-impedance and SI is ignored; resuming requires HOLD high while SCK remains low. This allows deterministic interruption-for example, to service a higher-priority interrupt-then seamless continuation of the same READ or WRITE sequence.

What is the endurance and data retention specification for AT25640AY1-10YI-2.7?

AT25640AY1-10YI-2.7 guarantees 1 million write/erase cycles and 100 years of data retention at 25°C. These specifications are validated across the full −40°C to +85°C operating range per AEC-Q100 stress testing. Real-world retention exceeds 30 years even at 85°C, making it suitable for applications where field replacement is impractical, such as embedded telemetry modules in remote infrastructure.