Microchip Technology 24AA01H-I/MS

Overview

24AA01H-I/MS 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 addresses 40h–7Fh. It supports byte and page writes (up to 8 bytes), delivers ≤1 mA read current and ≤1 μA standby current, and is housed in an 8-lead MSOP package.

For engineers reviewing the 24AA01H-I/MS datasheet, 24AA01H-I/MS pinout, 24AA01H-I/MS application, or 24AA01H-I/MS equivalent, key selection criteria include low-voltage operation down to 1.7V, half-array hardware write-protection via WP pin, Schmitt-trigger noise immunity on SDA/SCL, I²C bus compatibility at 100/400 kHz, and >1 million erase/write cycles with >200-year data retention.

Technical Context

The 24AA01H-I/MS implements a slave-only I²C interface with fixed 4-bit device address (1010b) and "don't care" A0–A2 pins-no internal connection-enabling single-device bus placement without address conflicts. Its internal architecture includes a page buffer (8-byte depth), address pointer auto-increment logic, and VCC threshold detector disabling write operations below 1.5V.

Write protection is implemented via the WP pin: tied to VSS enables full-array access; tied to VCC locks addresses 40h–7Fh (half-array), while permitting reads across the full 00h–7Fh range. Acknowledge polling is supported to detect write-cycle completion without timeout delays.

Key Specifications

Pinout & Package

24AA01H-I/MS uses an 8-lead MSOP (Micro Small Outline Package) with 0.65 mm lead pitch and exposed pad option not specified. Pin functions are electrically identical across PDIP, SOIC, TSSOP, and MSOP variants per Microchip DS22104A.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA01H-I/MS, the 24LC01BH-I/MS raises the minimum supply to 2.5V but adds E-temp support, while the AT24C01D-MAHM-T offers second-source assurance at minor write-time trade-off-both retain identical MSOP-8 footprint and I²C protocol behavior.

Availability

24AA01H-I/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, medical diagnostics, consumer configuration storage, and automotive body control modules requiring stable component supply across extended product lifecycles.

Supply support for 24AA01H-I/MS 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 design and manufacturing operations.

The 24AA01H belongs to Microchip's legacy serial EEPROM product line, designed specifically for cost-sensitive, low-power embedded systems requiring reliable, pin-compatible nonvolatile storage with minimal board space and bill-of-materials overhead.

FAQ

What is the minimum operating voltage for the 24AA01H-I/MS?

The 24AA01H-I/MS operates down to 1.7V DC, enabling direct integration with 1.8V logic families and battery-powered systems experiencing voltage sag. Below 1.5V, the internal VCC threshold detector disables write operations to prevent data corruption, though read functionality may remain active depending on actual VCC level and temperature.

How does the WP pin function on the 24AA01H-I/MS?

On the 24AA01H-I/MS, the WP (Write-Protect) pin provides hardware-level memory protection: when tied to VCC, addresses 40h–7Fh are write-inhibited while full-array reads remain enabled; when tied to VSS, full-array read/write is permitted. This enables secure storage of factory-calibrated data without software overhead.

Can the 24AA01H-I/MS be used in a multi-device I²C bus configuration?

Yes, the 24AA01H-I/MS supports multi-device I²C buses, but its A0–A2 pins have no internal connection and do not affect device addressing. All 24AA01H-I/MS units share the same fixed 7-bit slave address (1010xxx, where xxx are "don't care"), so only one 24AA01H-I/MS may reside on a given bus unless isolated by I²C multiplexer.

What is the maximum page write size for the 24AA01H-I/MS?

The 24AA01H-I/MS supports page writes of up to 8 bytes per STOP condition. The internal page buffer fills sequentially starting from the word address provided in the initial write command; exceeding 8 bytes causes wraparound within the same physical page (addresses 00h–07h, 08h–0Fh, etc.), potentially overwriting earlier data in that page.

Does the 24AA01H-I/MS require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA01H-I/MS requires external pull-up resistors on both SDA and SCL lines because its I²C interface uses open-drain outputs. 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.