Microchip Technology 24FC512T-I/ST

Overview

24FC512T-I/ST 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 1 MHz clock support, 128-byte page write buffer, and industrial temperature range (–40°C to +85°C). It delivers ultra-low standby current (1 µA max) and supports cascading up to eight devices on a single bus for expanded memory addressing in embedded control systems.

For engineers reviewing the 24FC512T-I/ST datasheet, 24FC512T-I/ST pinout, 24FC512T-I/ST application, or 24FC512T-I/ST equivalent, key selection criteria include its 1 MHz I²C speed at V_CC ≥ 2.5V, hardware write-protect (WP) pin, Schmitt-trigger noise immunity on SDA/SCL, and 1 µA standby current - critical for battery-backed data logging, firmware parameter storage, and industrial sensor node configuration.

Technical Context

The 24FC512T-I/ST implements a two-wire I²C interface with open-drain SDA/SCL pins requiring external pull-ups, and uses internal address pointer logic to enable current-address, random, and sequential read modes across the full 64K address space. Its page write architecture buffers up to 128 bytes before initiating a self-timed 5 ms erase/write cycle.

Hardware write protection is enforced via the WP pin sampled at the Stop bit of each write command; tying WP to V_CC disables all writes while preserving read access. The device integrates Schmitt-trigger inputs and slope-controlled outputs to suppress ground bounce and noise spikes, meeting robustness requirements in electrically noisy industrial environments.

Key Specifications

Pinout & Package

24FC512T-I/ST is packaged in an 8-lead SOIC (SOIJ/ST) with standard 150 mil body width and gull-wing leads. Pin 1 is marked with a notch or dot; the package is RoHS-compliant and lead-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA512T-I/ST and AT24C512-10PU-2.7, the 24FC512T-I/ST uniquely combines 1 MHz I²C speed at 1.7V operation, 1 million endurance cycles, and industrial temperature rating - making it optimal for next-generation battery-powered and high-reliability embedded systems requiring both performance and longevity.

Availability

24FC512T-I/ST is available at Aetrix Electronics and suitable for industrial sensor calibration storage, medical device configuration backup, and automotive body control module settings requiring stable component supply across extended product lifecycles.

Supply support for 24FC512T-I/ST 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, serving industrial, automotive, and consumer markets with high-reliability silicon and development tools.

The 24FC512T-I/ST belongs to Microchip's 24XX512 family of I²C EEPROMs, designed specifically for low-voltage, low-power, and noise-immune nonvolatile data storage in resource-constrained embedded systems.

FAQ

What is the maximum I²C clock frequency supported by the 24FC512T-I/ST?

The 24FC512T-I/ST supports up to 1 MHz I²C clock frequency when V_CC is 2.5V or higher. At V_CC below 2.5V (down to 1.7V), the maximum clock frequency is limited to 400 kHz. This dual-speed capability ensures compatibility with both legacy 400 kHz buses and modern high-throughput designs using the 24FC512T-I/ST.

How does the hardware write-protect (WP) pin function on the 24FC512T-I/ST?

The WP pin on the 24FC512T-I/ST is sampled at the Stop bit of each write command. When tied to V_CC, it disables all write operations (byte and page) while allowing unrestricted reads. When tied to V_SS, writes are enabled. This behavior is implemented in hardware and remains active regardless of power sequencing or MCU state - a key reliability feature of the 24FC512T-I/ST.

What is the page write buffer size of the 24FC512T-I/ST, and how does it affect write efficiency?

The 24FC512T-I/ST features a 128-byte page write buffer. This allows up to 128 bytes to be loaded into the buffer and written to memory in a single self-timed 5 ms cycle. Compared to byte-write mode, this reduces I²C transaction overhead by up to 128×, significantly accelerating bulk configuration updates - a core advantage of the 24FC512T-I/ST in production programming and field firmware patching.

Does the 24FC512T-I/ST support operation at 1.8V, and what are the implications?

Yes, the 24FC512T-I/ST is fully specified for operation down to 1.7V, including at 1.8V. At this voltage, it maintains full functionality: 128-byte page writes, 1 µA standby current, and 400 kHz I²C speed. This makes the 24FC512T-I/ST ideal for battery-powered IoT nodes and energy-harvesting systems where supply voltage may dip below 2.5V - a capability not shared by many competing EEPROMs.

How many devices can be connected to the same I²C bus using the 24FC512T-I/ST?

Up to eight 24FC512T-I/ST devices can be connected to a single I²C bus using the A0, A1, and A2 address pins. These three pins form a 3-bit chip address, allowing unique client addresses from 0x50 to 0x57 (base 0x50 + A2A1A0). This scalability enables modular memory expansion - for example, aggregating 4 Mbit total capacity - without bus arbitration complexity, a defining feature of the 24FC512T-I/ST.