Microchip Technology 24AA16-I/ST

Overview

24AA16-I/ST from Microchip Technology Inc. is a 16-Kbit I²C-compatible serial EEPROM organized as eight 256 × 8-bit blocks, operating from 1.7V to 5.5V with 400 kHz max clock frequency (100 kHz below 2.5V), 1 μA standby current, and industrial temperature range (–40°C to +85°C). It supports 16-byte page writes, hardware write-protection via WP pin, and is packaged in an 8-lead SOIC (ST).

For engineers reviewing the 24AA16-I/ST datasheet, 24AA16-I/ST pinout, 24AA16-I/ST application, or 24AA16-I/ST equivalent, key selection criteria include low-voltage operation down to 1.7V, Schmitt-trigger noise immunity on SDA/SCL, self-timed erase/write cycle, >1 million endurance cycles, and compatibility with standard I²C master controllers in space-constrained embedded systems.

Technical Context

The 24AA16-I/ST functions as a slave device on a two-wire I²C bus, using a 7-bit slave address format (1010xxxR/W) where the three block-select bits (B2–B0) determine one of eight 256-word memory blocks. Its internal Address Pointer auto-increments during sequential reads and page writes.

It implements Schmitt-trigger inputs and output slope control to suppress ground bounce and bus noise; supports ACK polling for write-cycle completion detection; and uses an on-chip page buffer to enable up to 16-byte writes within a single physical page boundary (0–15, 16–31, etc.), with wraparound behavior on boundary violation.

Key Specifications

Pinout & Package

24AA16-I/ST is housed in an 8-lead SOIC (Small Outline Integrated Circuit) package, 3.90 mm body width, with gull-wing leads and standard JEDEC MS-012AC footprint. Pin 1 is marked by a notch or bevel; exposed pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC16B-I/ST, the 24AA16-I/ST enables lower-voltage operation critical for battery-backed designs; compared with 24FC16-I/ST, it trades write speed for lower active current and broader legacy I²C compatibility.

Availability

24AA16-I/ST is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical diagnostics, and automotive body control modules requiring stable component supply, long-life data retention, and industrial-temperature reliability.

Supply support for 24AA16-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 devices, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA16 belongs to Microchip's 24XX16 family of I²C serial EEPROMs, designed specifically for low-power, space-constrained embedded systems requiring robust nonvolatile storage with minimal external components.

FAQ

What is the maximum I²C clock frequency supported by the 24AA16-I/ST?

The 24AA16-I/ST supports up to 400 kHz when VCC is 2.5V or higher; at VCC between 1.7V and 2.5V, the maximum clock frequency is reduced to 100 kHz to ensure timing margin compliance. This dual-speed behavior is built into the device's internal timing logic and requires no software configuration. The 24AA16-I/ST does not support 1 MHz operation - that capability is exclusive to the 24FC16 variant.

Does the 24AA16-I/ST require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA16-I/ST requires external pull-up resistors on both SDA and SCL because its I/O pins are open-drain. Recommended values are 10 kΩ for 100 kHz operation and 2 kΩ for 400 kHz. These resistors establish valid high logic levels and ensure proper I²C bus arbitration; omitting them will result in communication failure. The 24AA16-I/ST itself contains no internal pull-ups.

How does the Write-Protect (WP) pin function on the 24AA16-I/ST?

When the WP pin of the 24AA16-I/ST is tied to VCC, all write operations (byte and page) to the entire 16-Kbit memory array are inhibited; read operations remain fully functional. When WP is tied to VSS (or left floating, though not recommended), normal read/write access is enabled. This hardware-level protection operates independently of software commands and cannot be overridden - a key security feature for safeguarding critical configuration data in the 24AA16-I/ST.

What is the page size and write buffer depth of the 24AA16-I/ST?

The 24AA16-I/ST has a fixed page size of 16 bytes and an on-chip page write buffer capable of holding up to 16 bytes. During a page write, the device accepts up to 16 consecutive data bytes after the initial word address, then commits them atomically upon receipt of the Stop condition. Writing across a 16-byte boundary causes wraparound within the same page - the 24AA16-I/ST does not auto-advance to the next page.

Is the 24AA16-I/ST qualified for automotive applications?

Yes, the 24AA16-I/ST is AEC-Q100 qualified for automotive applications, meeting stress test requirements for temperature cycling, humidity, and electrical robustness. Its industrial temperature grade (–40°C to +85°C) and 200-year data retention align with automotive infotainment, body control, and telematics module lifecycles. However, it is not rated for under-hood engine control use - for those environments, Microchip offers extended-temperature variants like the 24AA16-E/ST.