Microchip Technology 24AA256T-I/MNY

Overview

24AA256T-I/MNY from Microchip Technology is a 256-Kbit I²C serial EEPROM with 32K × 8 organization, operating from 1.7V to 5.5V, supporting up to 400 kHz clock frequency, and rated for industrial temperature range (−40°C to +85°C). It features 64-byte page write buffer, hardware write-protection via WP pin, and Schmitt-trigger inputs for noise immunity - deployed in embedded system configuration storage, sensor calibration data retention, and power-fail-safe parameter logging.

For engineers reviewing the 24AA256T-I/MNY datasheet, 24AA256T-I/MNY pinout, 24AA256T-I/MNY application, or 24AA256T-I/MNY equivalent, key selection considerations include V_CC min (1.7V), page write time (≤5 ms), endurance (1M cycles), data retention (>200 years), and package-specific pin mapping for MNY (8-lead DFN).

Technical Context

The 24AA256T-I/MNY implements a two-wire I²C-compatible interface with open-drain SDA/SCL requiring external pull-ups, and uses internal address pointer logic for sequential reads across the full 0000h–7FFFh memory space. Its cascading capability supports up to eight devices on one bus using A0/A1/A2 chip-select bits.

It integrates Schmitt-trigger inputs on SDA/SCL for robust noise suppression, slope-controlled outputs to minimize ground bounce, and self-timed erase/write cycles with automatic page-buffer management. Write protection is hardware-enforced via the dedicated WP pin, sampled at the Stop bit of each write command.

Key Specifications

Pinout & Package

24AA256T-I/MNY is housed in an 8-lead DFN (Dual Flat No-lead) package with exposed thermal pad (can be connected to VSS or left floating), measuring 2 mm × 3 mm × 0.75 mm. Pin numbering follows JEDEC MS-012 standard, with pins arranged counterclockwise from the mark dot.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC256T-I/MNY, the 24AA256T-I/MNY enables lower-voltage operation critical for battery-powered nodes, while the 24AA256T-I/MS offers mechanical compatibility with legacy SOIC workflows - both retain identical memory architecture, timing, and I²C protocol behavior.

Availability

24AA256T-I/MNY is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, and smart energy metering requiring stable component supply across extended product lifecycles.

Supply support for 24AA256T-I/MNY 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 Inc. is a leading provider of microcontroller, mixed-signal, analog, and Flash-IP solutions, serving automotive, industrial, consumer, and communications markets with high-reliability silicon and development tools.

The 24AA256T-I/MNY belongs to Microchip's 24XX256 family of I²C EEPROMs, designed specifically for low-power, voltage-flexible nonvolatile data storage in space- and energy-constrained embedded systems.

FAQ

What is the minimum supply voltage required for reliable operation of the 24AA256T-I/MNY?

The 24AA256T-I/MNY operates reliably down to 1.7V across its full industrial temperature range (−40°C to +85°C). At V_CC < 2.5V, maximum I²C clock frequency is limited to 100 kHz. This low-voltage capability allows direct integration with 1.8V microcontrollers and energy-harvesting power supplies without level translation.

How does the WP pin function on the 24AA256T-I/MNY, and when is it sampled?

The WP (Write-Protect) pin on the 24AA256T-I/MNY is sampled at the Stop condition of each write command. When tied to VCC, it disables all write and erase operations while permitting unlimited reads. When tied to VSS, full read/write access is enabled. This sampling timing ensures deterministic protection even during partial bus transactions or power glitches.

Can the 24AA256T-I/MNY perform sequential reads across the entire 256-Kbit memory space?

Yes, the 24AA256T-I/MNY supports sequential reads across the full 0000h–7FFFh address range. After transmitting the initial address and receiving the first byte, the internal address pointer auto-increments. Upon reaching address 7FFFh, it rolls over to 0000h - enabling continuous streaming of stored configuration or log data without host-side address management.

What is the maximum number of 24AA256T-I/MNY devices that can be connected to a single I²C bus?

Up to eight 24AA256T-I/MNY devices can be connected to one I²C bus using unique combinations of the A0, A1, and A2 address pins. Each device responds only to its assigned 3-bit chip address (bits A2–A0 in the I²C control byte), enabling scalable memory expansion up to 2 Mbit total address space without additional address decoding logic.

Does the 24AA256T-I/MNY require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA256T-I/MNY has open-drain SDA and SCL pins and requires external pull-up resistors to VCC. Recommended values are 2 kΩ for 400 kHz operation and 10 kΩ for 100 kHz. Pull-up strength directly affects rise time compliance per AC specifications - undersized resistors may violate t_R limits and cause communication failures.