Microchip Technology 24AA02HT-I/LT

Overview

24AA02HT-I/LT from Microchip Technology is a 2 Kbit I²C-compatible serial EEPROM organized as 256 × 8-bit memory with hardware write-protect for the upper half-array (addresses 0x80–0xFF), 1.7V to 5.5V supply operation, and industrial temperature range (−40°C to +85°C). It features Schmitt-trigger inputs, output slope control, 8-byte page write buffer, and supports 100 kHz/400 kHz clock rates depending on VCC.

For engineers reviewing the 24AA02HT-I/LT datasheet, 24AA02HT-I/LT pinout, 24AA02HT-I/LT application, or 24AA02HT-I/LT equivalent, key selection criteria include low-voltage operation down to 1.7V, half-array hardware write-protection via WP pin, I²C bus timing compliance across voltage ranges, and AEC-Q100 qualification for automotive use cases.

Technical Context

The 24AA02HT-I/LT implements a two-wire I²C interface with fixed 7-bit client address (1010xxx) and R/W bit, supporting byte and page write modes. Its internal Address Pointer auto-increments during sequential reads and random-access operations, enabling efficient memory traversal without repeated address retransmission.

Write protection is implemented via the WP pin: tied to VSS enables full-array writes; tied to VCC disables writes to addresses 0x80–0xFF while permitting full-array reads. The device uses Schmitt-trigger inputs and input filtering (50 ns spike suppression) to ensure robust operation on noisy buses, with no internal connections to A0/A1/A2 pins.

Key Specifications

Pinout & Package

The 24AA02HT-I/LT is packaged in an 8-lead MSOP (LT) with exposed pad, measuring 3.0 mm × 3.0 mm × 0.95 mm. Pin 1 is marked by a dot or beveled corner; the exposed pad may be connected to VSS or left floating per layout requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC02BHT-I/LT and AT24C02C-SSHM-T, the 24AA02HT-I/LT uniquely combines 1.7V operation, AEC-Q100 qualification, and 1 million write cycles - making it the only option qualified for automotive and ultra-low-voltage industrial applications requiring long-term reliability.

Availability

24AA02HT-I/LT is available at Aetrix Electronics and suitable for automotive ECUs, industrial sensor nodes, medical device configuration storage, and network equipment requiring stable component supply with guaranteed long-term availability.

Supply support for 24AA02HT-I/LT 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, serving automotive, industrial, communications, and consumer markets with vertically integrated design and manufacturing.

The 24AA02H family was designed specifically for secure, low-voltage, automotive-qualified serial EEPROM applications - emphasizing robustness, factory programmability, and seamless integration into I²C-based embedded systems.

FAQ

What is the operating voltage range for the 24AA02HT-I/LT?

The 24AA02HT-I/LT operates from 1.7V to 5.5V, enabling compatibility with 1.8V logic systems, 3.3V microcontrollers, and legacy 5V designs. This wide range eliminates the need for external level shifters in mixed-voltage systems and supports battery-powered applications down to single-cell Li-ion or alkaline operation.

How does the WP pin function on the 24AA02HT-I/LT?

The WP pin on the 24AA02HT-I/LT controls hardware write-protection: when tied to VCC, writes to memory addresses 0x80–0xFF are inhibited while reads remain fully enabled; when tied to VSS, full read/write access is granted. This allows permanent protection of critical data like MAC addresses or calibration constants without software overhead.

Is the 24AA02HT-I/LT pin-compatible with other 24XX02H variants?

Yes, the 24AA02HT-I/LT shares identical pinout, package dimensions, and electrical interface with all 24XX02H family members including 24LC02BH and 24AA02H in the same LT (MSOP) package. A0, A1, and A2 pins are NC across the family, ensuring drop-in replacement where voltage and qualification requirements align.

What is the maximum I²C clock frequency supported by the 24AA02HT-I/LT?

The 24AA02HT-I/LT supports up to 400 kHz I²C clock frequency when VCC is 2.5V or higher. At VCC between 1.7V and 2.5V, the maximum clock rate is 100 kHz. These limits are enforced by internal timing circuits and must be observed to guarantee reliable data transfer and acknowledge generation.

Does the 24AA02HT-I/LT require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA02HT-I/LT requires external pull-up resistors on both SDA and SCL lines because its I/O pins are open-drain. Recommended values are 2 kΩ for 400 kHz operation and 10 kΩ for 100 kHz, connected to the same VCC rail used by the device to ensure proper logic levels and rise time compliance.