Microchip Technology 24AA512-I/ST14

Overview

24AA512-I/ST14 from Microchip Technology Inc. is a 512 Kbit (64K × 8) I²C-compatible serial EEPROM with industrial temperature range (–40°C to +85°C), 1.7V–5.5V supply operation, 400 kHz max clock frequency, and hardware write-protection via the WP pin. It features a 128-byte page write buffer, Schmitt-trigger inputs for noise immunity, and supports up to eight devices on a single I²C bus in embedded control and data-logging systems.

For engineers reviewing the 24AA512-I/ST14 datasheet, 24AA512-I/ST14 pinout, 24AA512-I/ST14 application, or 24AA512-I/ST14 equivalent, key selection considerations include low-voltage operation down to 1.7V, 1 µA standby current, page write timing ≤5 ms, I²C address configuration via A0–A2 pins, and compatibility with standard 2-wire bus protocols in space-constrained industrial designs.

Technical Context

The 24AA512-I/ST14 implements a two-wire I²C interface with open-drain SDA/SCL lines requiring external pull-ups, and uses internal address pointer logic to support current-address, random, and sequential read modes across its full 0x0000–0xFFFF memory map. Its architecture includes a 128-byte page latch buffer and self-timed erase/write cycles managed by on-chip control logic.

Hardware write protection is enforced solely by the WP pin state at the Stop condition of each write command; no software lock or register-based protection is present. The device employs Schmitt-trigger inputs on SDA and SCL with ≥50 ns spike suppression and hysteresis ≥0.05×VCC, enabling robust operation in electrically noisy environments without external filtering.

Key Specifications

Pinout & Package

The 24AA512-I/ST14 is supplied in a 14-lead TSSOP package (ST14), with lead pitch of 0.65 mm and body dimensions 5.0 mm × 6.4 mm × 1.2 mm. Pin 1 is marked by a notch or dot; pins 9–14 are NC (no connect) and must remain unconnected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC512-I/ST14 and AT24C512-10PU-2.7, the 24AA512-I/ST14 uniquely supports 1.7V operation and 400 kHz I²C speed in the same ST14 package, making it optimal for low-power, fast-boot embedded systems where voltage headroom and bus efficiency are constrained.

Availability

24AA512-I/ST14 is available at Aetrix Electronics and suitable for industrial sensor calibration storage, medical device configuration memory, automotive body control modules, and smart energy meter event logging requiring stable component supply and long-term lifecycle assurance.

Supply support for 24AA512-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 microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 24AA512 belongs to Microchip's serial EEPROM product line, designed specifically for reliable, low-power, I²C-based 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 24AA512-I/ST14?

The 24AA512-I/ST14 supports up to 400 kHz I²C clock frequency when VCC is ≥2.5V. At VCC < 2.5V (e.g., 1.8V operation), the maximum clock rate is limited to 100 kHz. This dual-speed capability allows flexible integration across 1.8V, 2.5V, 3.3V, and 5V systems while maintaining timing compliance per I²C specification. The 24AA512-I/ST14 does not support 1 MHz operation - that capability is exclusive to the 24FC512 variant.

How does the WP pin function on the 24AA512-I/ST14?

The WP (Write-Protect) pin on the 24AA512-I/ST14 is a hardware-level enable that globally inhibits all write operations when pulled high to VCC. When tied to VSS, writes are fully enabled. The pin state is sampled only at the Stop condition of each write command - toggling WP during an active cycle has no effect. This provides deterministic, glitch-immune protection against unintended writes during power transitions. The 24AA512-I/ST14 does not support software-controlled or partial-array write protection.

Can multiple 24AA512-I/ST14 devices share the same I²C bus?

Yes, up to eight 24AA512-I/ST14 devices can operate on a single I²C bus using hard-wired A0, A1, and A2 address pins to generate unique 3-bit chip addresses (1010 A2 A1 A0 R/W). Each device responds only to its configured address, enabling scalable memory expansion to 4 Mbit total. No additional arbitration or protocol changes are needed - standard I²C addressing and ACK/NACK handling apply. The 24AA512-I/ST14 requires no external address decoding logic.

What is the page write buffer size and how does it affect programming efficiency?

The 24AA512-I/ST14 features a 128-byte page write buffer, allowing up to 128 bytes to be loaded into the latch and written to memory in a single self-timed cycle (≤5 ms). This reduces I²C bus overhead compared to byte-wise writes - for example, writing 128 bytes takes one Start/Stop sequence instead of 128. However, page writes cannot cross physical page boundaries (every 128-byte aligned address), so software must manage alignment to avoid data wraparound. The 24AA512-I/ST14 does not support partial-page writes without refreshing unchanged bytes.

Is the 24AA512-I/ST14 qualified for automotive applications?

Yes, the 24AA512-I/ST14 is AEC-Q100 qualified for automotive applications, meeting Grade 2 temperature requirements (–40°C to +105°C ambient, validated to +125°C junction). While the "I" suffix denotes Industrial grade (–40°C to +85°C), the underlying die and qualification testing satisfy AEC-Q100 stress test standards including HTOL, TCT, and ESD. This makes the 24AA512-I/ST14 suitable for body electronics, infotainment, and ADAS subsystems where extended reliability is required but full automotive-grade packaging is not mandated.