Microchip Technology 24AA512T-I/ST14

Overview

24AA512T-I/ST14 from Microchip Technology Inc. is a 512 Kbit I²C-compatible serial EEPROM organized as 64K × 8-bit, operating from 1.7V to 5.5V with industrial temperature range (–40°C to +85°C). It features 128-byte page write buffer, hardware write-protect (WP), Schmitt-trigger inputs, and supports up to eight devices on one bus. Used in embedded systems for firmware storage, calibration data retention, and configuration parameter backup.

For engineers reviewing the 24AA512T-I/ST14 datasheet, 24AA512T-I/ST14 pinout, 24AA512T-I/ST14 application, or 24AA512T-I/ST14 equivalent, key selection criteria include low-voltage operation down to 1.7V, 400 kHz max clock frequency at V_CC ≥ 2.5V, 1 µA standby current, 128-byte page write capability, and 14-lead TSSOP package compatibility with board-level noise immunity requirements.

Technical Context

The 24AA512T-I/ST14 implements a two-wire I²C interface with open-drain SDA/SCL pins requiring external pull-ups, and uses internal address pointer logic for sequential, random, and current-address read modes. Its memory array is partitioned into 128-byte pages, with self-timed erase/write cycles and automatic address rollover at FFFF_H.

Hardware write protection is controlled solely by the WP pin state at Stop condition sampling; no internal register control exists. Schmitt-trigger inputs on SDA and SCL provide 50 ns spike suppression and hysteresis of 0.05×V_CC, enabling reliable operation in electrically noisy environments without external filtering.

Key Specifications

Pinout & Package

24AA512T-I/ST14 is housed in a 14-lead Thin Shrink Small Outline Package (TSSOP), 5.0 mm × 6.4 mm body, 0.65 mm pitch, with exposed pad optional for thermal relief or grounding. Pin 1 is marked with a dot; pins are numbered counter-clockwise from top-left corner when viewed from top.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC512-I/ST14, the 24AA512T-I/ST14 offers lower-voltage operation critical for 1.8V systems, while AT24C512-10TU-2.7 trades hardware write-protection and noise immunity for faster clock support and smaller footprint - making each alternative suitable only under specific voltage, reliability, or layout constraints.

Availability

24AA512T-I/ST14 is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, and automotive body control modules requiring stable component supply, long-term data retention, and AEC-Q100-aligned reliability.

Supply support for 24AA512T-I/ST14 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 microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA512 belongs to Microchip's 24XX512 family of I²C serial EEPROMs, designed specifically for robust, low-power nonvolatile data storage in industrial, automotive, and medical applications demanding extended temperature operation and high endurance.

FAQ

What is the maximum I²C clock frequency supported by the 24AA512T-I/ST14?

The 24AA512T-I/ST14 supports up to 400 kHz when V_CC is 2.5V or higher. At V_CC below 2.5V (down to 1.7V), the maximum clock frequency is reduced to 100 kHz to ensure timing margin compliance. This dual-speed capability allows interoperability across mixed-voltage I²C systems without protocol changes. The 24AA512T-I/ST14 does not support 1 MHz operation - that capability is exclusive to the 24FC512 variant.

Does the 24AA512T-I/ST14 have hardware write protection, and how is it implemented?

Yes, the 24AA512T-I/ST14 includes dedicated hardware write protection via the WP pin. When WP is tied to V_CC, all write operations (byte and page) are inhibited while reads remain fully functional. The WP state is sampled only at the Stop condition of each write command, making it immune to transient noise. This differs from software-based protection and ensures fail-safe data integrity even during MCU resets or firmware crashes - a key feature of the 24AA512T-I/ST14.

What package type is used for the 24AA512T-I/ST14, and what are its key mechanical dimensions?

The 24AA512T-I/ST14 uses a 14-lead Thin Shrink Small Outline Package (TSSOP) with body dimensions of 5.0 mm × 6.4 mm and 0.65 mm lead pitch. It features an exposed pad (optional for thermal or grounding use) and conforms to JEDEC MO-153. Pin 1 is marked with a dot; pins 9–14 are NC (no connect) and must remain unconnected or grounded per layout guidelines. This package is distinct from the 8-lead variants used by other members of the 24XX512 family.

How many devices can be connected on the same I²C bus using the 24AA512T-I/ST14?

Up to eight 24AA512T-I/ST14 devices can share a single I²C bus using the three hardware address pins A0, A1, and A2. Each combination of logic levels (0 or 1) on these pins generates a unique 3-bit chip address, allowing full 7-bit client addressing (1010 A2 A1 A0 R/W). This enables scalable memory expansion up to 4 Mbit total capacity without additional address decoding logic - a core architectural feature of the 24AA512T-I/ST14.

What is the page write buffer size of the 24AA512T-I/ST14, and why does it matter for system performance?

The 24AA512T-I/ST14 has a 128-byte page write buffer. This means up to 128 bytes can be loaded into the internal latch and written to memory in a single self-timed cycle (≤5 ms), significantly reducing total programming time versus individual byte writes. For example, writing 128 bytes takes one 5 ms cycle instead of 128 × 5 ms. This directly lowers host CPU overhead, improves firmware update throughput, and minimizes bus occupancy - a critical advantage in real-time embedded systems using the 24AA512T-I/ST14.