Microchip Technology 24AA01HT-I/SN

Overview

24AA01HT-I/SN from Microchip Technology Inc. is a 1 Kbit I²C-compatible serial EEPROM organized as 128 × 8-bit memory, operating from 1.7V to 5.5V with industrial temperature range (−40°C to +85°C), 400 kHz max clock frequency, and hardware write-protect for half-array (addresses 40h–7Fh). It supports page writes of up to 8 bytes and delivers >1 million erase/write cycles with >200 years data retention - used in embedded system configuration storage, sensor calibration data logging, and firmware parameter backup.

For engineers reviewing the 24AA01HT-I/SN datasheet, 24AA01HT-I/SN pinout, 24AA01HT-I/SN application, or 24AA01HT-I/SN equivalent, key selection criteria include low-voltage operation down to 1.7V, Schmitt-trigger noise immunity on SDA/SCL, 1 μA standby current, and half-array hardware write-protection via WP pin - all critical for battery-powered and automotive-grade designs requiring robust nonvolatile memory.

Technical Context

The 24AA01HT-I/SN implements a slave-only I²C interface with fixed 7-bit device address prefix '1010' and three "don't care" bits, enabling single-device bus operation without address conflicts. Its internal address pointer auto-increments during sequential reads and page writes, supporting current-address, random, and sequential read modes.

Write protection is implemented via the WP pin: tied to VCC, it disables writes to addresses 40h–7Fh while permitting full read access; tied to VSS, full read/write is enabled. The device uses an on-chip HV generator for EEPROM programming and includes VCC threshold detection (<1.5V) to inhibit writes during brown-out conditions.

Key Specifications

Pinout & Package

24AA01HT-I/SN is supplied in an 8-lead plastic SOIC package (3.90 mm body width), RoHS-compliant and Pb-free. Pin 1 is A0 (NC), Pin 2 is A1 (NC), Pin 3 is A2 (NC), Pin 4 is VSS (ground), Pin 5 is SDA (bidirectional open-drain I²C data line), Pin 6 is SCL (input-only I²C clock), Pin 7 is WP (write-protect input), and Pin 8 is VCC (1.7–5.5V supply).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA01HT-I/SN, the 24LC01BHT-I/SN trades lower voltage support for broader automotive qualification, while the AT24C01C-SSHM-T offers identical voltage range but removes hardware-level memory segmentation - making 24AA01HT-I/SN uniquely suited for mixed-access configurations requiring physical write-locking.

Availability

24AA01HT-I/SN is available at Aetrix Electronics and suitable for industrial sensor nodes, automotive body control modules, medical handheld diagnostics, smart energy meters, and battery-backed configuration storage requiring stable component supply across extended product lifecycles.

Supply support for 24AA01HT-I/SN 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 24AA01H/24LC01BH family was designed specifically for cost-sensitive, space-constrained embedded systems requiring reliable, low-power, I²C-compatible nonvolatile memory with hardware write protection - targeting industrial, medical, and consumer applications.

FAQ

What is the minimum supply voltage required for reliable operation of the 24AA01HT-I/SN?

The 24AA01HT-I/SN operates reliably down to 1.7V across its full industrial temperature range (−40°C to +85°C). Below this threshold, the internal VCC detector disables write operations to prevent data corruption. This makes the 24AA01HT-I/SN suitable for direct integration with 1.8V logic families and battery-powered systems where voltage droop occurs during peak load.

How does the WP pin function on the 24AA01HT-I/SN, and what memory regions does it protect?

On the 24AA01HT-I/SN, the WP pin provides hardware-level write protection: when tied to VCC, writes to memory addresses 40h–7Fh (64 bytes, upper half of the 128-byte array) are inhibited, while reads remain fully functional. When tied to VSS, full read/write access is enabled across the entire 00h–7Fh address space. This enables secure storage of calibration constants or firmware keys in the protected region.

Can the 24AA01HT-I/SN perform page writes, and what is the maximum number of bytes per page?

Yes, the 24AA01HT-I/SN supports page writes of up to 8 bytes per transaction. The device uses an internal 8-byte page buffer; after the master sends the word address and first data byte, it may transmit up to seven additional bytes before issuing a STOP condition. All 8 bytes are written simultaneously during the internal 3 ms write cycle - reducing I²C bus occupancy versus eight separate byte writes.

What is the endurance rating of the 24AA01HT-I/SN, and how is it validated?

The 24AA01HT-I/SN is rated for more than 1 million erase/write cycles at 25°C and VCC = 5.5V under block-mode stress testing. This endurance is ensured through characterization (not 100% tested per unit) and correlates with Microchip's Total Endurance™ Model, which predicts real-world wear based on voltage, temperature, and usage patterns - enabling accurate lifetime estimation in field-deployed systems.

Is the 24AA01HT-I/SN compatible with standard I²C protocols, and what are its timing constraints at 400 kHz?

Yes, the 24AA01HT-I/SN is fully I²C-compatible and supports standard-mode (100 kHz) and fast-mode (400 kHz) operation. At 400 kHz and VCC ≥ 2.5V, it requires minimum SCL high time of 600 ns, SCL low time of 1300 ns, and SDA setup/hold times of 100 ns/0 ns respectively - meeting I²C specification requirements for interoperability with all compliant masters including PIC® MCUs, ARM-based SoCs, and Linux I²C drivers.