Microchip Technology AT25320AY1-10YI-2.7

Overview

AT25320AY1-10YI-2.7 from Microchip Technology (formerly Atmel) is a 32-Kbit SPI serial EEPROM organized as 4096 × 8 bits, operating from 2.7V to 5.5V with 20 MHz max clock rate at 5V, 32-byte page write capability, and automotive-grade industrial temperature range (−40°C to +85°C). It serves as nonvolatile configuration storage in microcontroller-based automotive control modules, sensor calibration systems, and industrial PLCs.

For engineers reviewing the AT25320AY1-10YI-2.7 datasheet, AT25320AY1-10YI-2.7 pinout, AT25320AY1-10YI-2.7 application, or AT25320AY1-10YI-2.7 equivalent, key selection criteria include its 8-lead MAP package footprint, hardware/software write protection via WP pin and status register, 1 million write cycles endurance, 100-year data retention, and support for SPI Modes 0 and 3 in low-voltage operation.

Technical Context

The AT25320AY1-10YI-2.7 implements a synchronous slave SPI interface with dedicated SI/SO lines, CS-controlled selection, and HOLD pin for pausing serial transfers without reset. Its internal architecture includes an 8-bit instruction register supporting WREN/WRDI/RDSR/WRSR/READ/WRITE op-codes, with MSB-first data framing and automatic address increment during sequential reads.

Block write protection is managed through nonvolatile BP0/BP1 bits in the status register, enabling selective protection of 0%, 25%, 50%, or 100% of the memory array. The WPEN bit controls hardware write protection activation, and all programming cycles are self-timed with no separate erase step required.

Key Specifications

Pinout & Package

AT25320AY1-10YI-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 M95320-DRMN3TP/K and BR24T32FJ-WE2, the AT25320AY1-10YI-2.7 uniquely combines HOLD pin support, MAP package for space-constrained designs, and guaranteed 20 MHz operation at 2.7V–5.5V-making it optimal for automotive and industrial systems demanding both speed and physical compactness.

Availability

AT25320AY1-10YI-2.7 is available at Aetrix Electronics and suitable for automotive control units, industrial PLCs, medical sensor calibration modules, and smart energy meters requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for AT25320AY1-10YI-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 leader in microcontrollers, analog, FPGA, and memory solutions, acquired Atmel in 2016 and maintains full product support for legacy Atmel EEPROMs.

The AT25320AY1-10YI-2.7 belongs to Microchip's AT25xxx family of SPI serial EEPROMs, designed specifically for reliable, low-power nonvolatile storage in automotive, industrial, and medical systems where write endurance, data retention, and robust interface control are critical.

FAQ

What is the maximum clock frequency supported by the AT25320AY1-10YI-2.7 at 3.3V supply?

The AT25320AY1-10YI-2.7 supports up to 10 MHz at VCC = 2.7V–3.6V per AC Characteristics Table (page 5). This is confirmed in the "AC Characteristics" section where fSCK Max = 10 MHz for 2.7–5.5V range. Operation above 10 MHz at 3.3V violates timing specifications and may cause read/write failures. Always reference the voltage-specific timing table when designing clock trees.

Does the AT25320AY1-10YI-2.7 require an external pull-up resistor on the SO pin?

No, the AT25320AY1-10YI-2.7 does not require an external pull-up on SO. Its SO pin is actively driven high or low during valid output periods and enters high-impedance state when CS is high or HOLD is asserted. External pull-ups would interfere with tri-state behavior and are explicitly omitted in all functional timing diagrams and application schematics in the datasheet.

How is write protection configured on the AT25320AY1-10YI-2.7 - via hardware pin only or also software-controllable?

Write protection on the AT25320AY1-10YI-2.7 is configurable via both hardware and software: the WP pin provides hardware-level lock when WPEN=1, while the status register's BP0/BP1 bits (set via WRSR instruction) define which memory blocks are protected. Both mechanisms operate concurrently - e.g., WP low + WPEN=1 blocks all status register writes, regardless of BP bits. This dual-layer scheme is detailed in Tables 4 and 5 of the datasheet.

Can the AT25320AY1-10YI-2.7 be used in SPI Mode 1 or Mode 2, or is it limited to Modes 0 and 3?

The AT25320AY1-10YI-2.7 is explicitly specified for SPI Modes 0 (CPOL=0, CPHA=0) and 3 (CPOL=1, CPHA=1) only, as stated in the Features section. It does not support Mode 1 (CPOL=0, CPHA=1) or Mode 2 (CPOL=1, CPHA=0). Attempting Mode 1/2 operation will result in incorrect sampling of SI or unstable SO output due to mismatched clock edge alignment.

What is the purpose of the HOLD pin on the AT25320AY1-10YI-2.7, and how must it be used correctly?

The HOLD pin on the AT25320AY1-10YI-2.7 suspends ongoing SPI communication without resetting the internal address counter or instruction state. To use it correctly: assert HOLD low only when SCK is low; maintain HOLD low until ready to resume; then release HOLD while SCK remains low. If SCK toggles during HOLD, the device ignores SI and holds SO in high-Z. This behavior is defined in the "HOLD" subsection on page 7 of the datasheet.