Microchip Technology 24LC256T-E/MNY

Overview

24LC256T-E/MNY from Microchip Technology is a 256-Kbit I²C serial EEPROM with 32K × 8 organization, operating from 2.5V to 5.5V, supporting up to 400 kHz clock frequency, and rated for industrial temperature range (–40°C to +85°C). It features hardware write-protection via the WP pin, 64-byte page write buffer, and Schmitt-trigger inputs for noise immunity - deployed in embedded systems requiring nonvolatile parameter storage, such as industrial sensor calibration and power supply configuration.

For engineers reviewing the 24LC256T-E/MNY datasheet, 24LC256T-E/MNY pinout, 24LC256T-E/MNY application, or 24LC256T-E/MNY equivalent, key selection criteria include VCC compatibility (2.5–5.5V), I²C timing compliance at 400 kHz, page write time ≤5 ms, hardware write-protect functionality, and MNY package (8-lead TSSOP) mechanical fit.

Technical Context

The 24LC256T-E/MNY implements a two-wire I²C-compatible interface with open-drain SDA/SCL pins requiring external pull-ups. Its internal address counter supports sequential reads across the full 32K-word space, while cascading up to eight devices on one bus is enabled by A0–A2 chip-select inputs.

It uses low-power CMOS technology with ≤3 mA write current and ≤1 µA standby current (I-temp), and integrates slope-controlled outputs to suppress ground bounce. The device performs self-timed erase/write cycles and supports both byte and page write modes, with page boundaries aligned to 64-byte offsets.

Key Specifications

Pinout & Package

24LC256T-E/MNY is packaged in an 8-lead TSSOP (MNY), with 3.0 mm × 4.4 mm body, 0.65 mm lead pitch, and exposed pad optional for thermal relief. Pin functions are validated per Microchip DS20001203Y, Table 2-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA256-I/MNY and AT24C256-10TU-2.7, the 24LC256T-E/MNY provides optimal balance of industrial temperature rating, proven 400 kHz timing margin, and cost-effective 2.5–5.5V operation - making it ideal for fixed-voltage embedded systems where extended voltage range or ultra-high speed are unnecessary.

Availability

24LC256T-E/MNY is available at Aetrix Electronics and suitable for industrial sensor calibration, power supply configuration, and medical device settings requiring stable component supply and guaranteed long-term availability.

Supply support for 24LC256T-E/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 vertically integrated silicon and development tools.

The 24LC256T-E/MNY belongs to Microchip's 24XX256 family of I²C serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in space- and power-constrained embedded systems.

FAQ

What is the maximum I²C clock frequency supported by the 24LC256T-E/MNY?

The 24LC256T-E/MNY supports a maximum I²C clock frequency of 400 kHz when VCC is ≥2.5V. This is specified in Microchip's DS20001203Y datasheet, Table 1-2. Operation at 100 kHz is required only when VCC drops below 2.5V - which does not apply to the 24LC256T-E/MNY due to its 2.5V minimum supply rating. The 24LC256T-E/MNY is not rated for 1 MHz operation; that capability is exclusive to the 24FC256 variant.

Does the 24LC256T-E/MNY support page write operations, and what is the buffer size?

Yes, the 24LC256T-E/MNY supports page write operations with a 64-byte page write buffer. This allows up to 64 bytes to be loaded into the on-chip latch and written to memory in a single self-timed cycle (≤5 ms). Page writes improve efficiency versus byte writes by reducing I²C start/stop overhead. The 24LC256T-E/MNY enforces strict page boundaries: crossing a 64-byte boundary causes wraparound within the same page, so software must manage alignment.

How does the Write-Protect (WP) pin function on the 24LC256T-E/MNY?

The WP pin on the 24LC256T-E/MNY is sampled at the Stop bit of each write command. When tied to VCC, it disables all write operations (byte, page, or erase) across the full 0x0000–0x7FFF address space, while read operations remain fully functional. When tied to VSS, writes are enabled. The 24LC256T-E/MNY does not support partial-array write protection - the WP pin is an all-or-nothing hardware lock, providing simple, deterministic safeguarding of stored configuration data.

What package type is used for the 24LC256T-E/MNY, and what are its key mechanical features?

The 24LC256T-E/MNY uses the MNY package: an 8-lead TSSOP (Thin Shrink Small Outline Package) with 3.0 mm × 4.4 mm body dimensions, 0.65 mm lead pitch, and gull-wing leads. It is RoHS compliant and rated for industrial temperature (–40°C to +85°C). The MNY package is surface-mount compatible, offers good thermal performance, and is widely supported by automated assembly processes - distinguishing it from PDIP, SOIC, or DFN variants of the same device.

Is the 24LC256T-E/MNY AEC-Q100 qualified, and what temperature range does it support?

No, the 24LC256T-E/MNY is not AEC-Q100 qualified. It is rated for the industrial temperature range (–40°C to +85°C), denoted by the "I" suffix in its ordering code. While the broader 24XX256 family includes AEC-Q100-qualified variants (e.g., 24LC256T-E/SM with "E" for extended temp and automotive qualification), the MNY package variant carries the "I" grade. For automotive applications requiring AEC-Q100 compliance, designers should select the SM (8-lead SOIJ) or ST (8-lead SOIC) variants explicitly marked with automotive qualification.