Microchip Technology 24AA08T-I/ST

Overview

24AA08T-I/ST from Microchip Technology Inc. is an 8-Kbit I²C-compatible serial EEPROM organized as four 256 × 8-bit blocks, operating from 1.7V to 5.5V with 400 kHz max clock frequency, 1 µA standby current, and industrial temperature range (–40°C to +85°C). It features hardware write-protection via the WP pin, 16-byte page write buffer, and Schmitt-trigger inputs for noise immunity - deployed in embedded system configuration storage and sensor calibration data retention.

For engineers reviewing the 24AA08T-I/ST datasheet, 24AA08T-I/ST pinout, 24AA08T-I/ST application, or 24AA08T-I/ST equivalent, key selection considerations include its 1.7V low-voltage operation, I²C bus compatibility up to 400 kHz, 8-lead SOIC package (ST suffix), hardware write-protect functionality, and 1 million endurance cycles - critical for battery-powered and industrial control designs requiring nonvolatile parameter storage.

Technical Context

The 24AA08T-I/ST implements a two-wire I²C interface with open-drain SDA/SCL pins requiring external pull-ups, supports standard-mode (100 kHz) and fast-mode (400 kHz) signaling, and uses a 4-bit device code (1010) with 2-bit block select (B1/B0) to address its four 256-word memory blocks. Its internal Address Pointer auto-increments during sequential reads and enables current-address and random-access read modes.

Write operations include byte-write and 16-byte page-write with self-timed erase/write cycles (≤5 ms), while hardware write-protection is controlled by the WP pin tied to VCC (protection enabled) or VSS (protection disabled); the SOIC package fully supports WP functionality, unlike CSP variants.

Key Specifications

Pinout & Package

24AA08T-I/ST is packaged in an 8-lead SOIC (SN) with 3.90 mm body width, JEDEC MS-012AC compliant, and marked "24AA08T-I/ST" on top surface. The exposed pad is not present in this SOIC variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC08BT-I/ST, the 24AA08T-I/ST enables 1.7V operation critical for ultra-low-power designs; versus 24FC08T-I/ST, it trades 1 MHz speed for broader legacy I²C controller compatibility while maintaining identical package, pinout, and endurance.

Availability

24AA08T-I/ST is available at Aetrix Electronics and suitable for industrial PLC configuration storage, medical device calibration data retention, and automotive body control module settings requiring stable component supply across extended production lifecycles.

Supply support for 24AA08T-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, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 24AA08T-I/ST belongs to Microchip's 24XX08 family of I²C serial EEPROMs, designed specifically for cost-sensitive, low-power embedded systems requiring reliable nonvolatile storage with minimal board space and interface complexity.

FAQ

What is the maximum I²C clock frequency supported by the 24AA08T-I/ST?

The 24AA08T-I/ST supports up to 400 kHz in fast-mode operation 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 capability allows flexible integration across 1.8V, 3.3V, and 5V system buses without external clock dividers or protocol adaptation.

Does the 24AA08T-I/ST require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA08T-I/ST requires external pull-up resistors on both SDA and SCL lines because its I²C interface uses open-drain outputs. Typical values are 10 kΩ for 100 kHz operation and 2 kΩ for 400 kHz, selected based on bus capacitance and rise-time requirements. Failure to install pull-ups will prevent proper I²C communication and device addressing.

How does the WP pin function on the 24AA08T-I/ST?

The WP (Write-Protect) pin on the 24AA08T-I/ST enables hardware-level memory protection: tying WP to VCC disables all write operations to the entire 8-Kbit array while permitting unrestricted reads; tying WP to VSS enables full read/write access. This feature is fully implemented in the SOIC package and provides tamper-resistant configuration locking independent of firmware state.

What is the memory organization of the 24AA08T-I/ST?

The 24AA08T-I/ST organizes its 8-Kbit capacity as four independent blocks of 256 × 8-bit words (total 1024 bytes), addressed using a 4-bit device code (1010) and 2-bit block-select bits (B1/B0) in the I²C control byte. This structure allows isolated access to distinct configuration zones - for example, separating calibration data, user preferences, and firmware metadata - without cross-block interference.

Is the 24AA08T-I/ST RoHS compliant and AEC-Q100 qualified?

Yes, the 24AA08T-I/ST is RoHS compliant per EU Directive 2011/65/EU and AEC-Q100 qualified for automotive applications. Its industrial temperature grade (–40°C to +85°C), 1 million endurance cycles, and >200-year data retention meet stringent reliability requirements for under-hood and body-control modules, making it suitable for both automotive and industrial deployments.