Microchip Technology 24AA08H-I/MS

Overview

24AA08H-I/MS 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 industrial temperature range (–40°C to +85°C) and housed in an 8-lead MSOP package. It features hardware write-protection for half the memory array (200h–3FFh), 16-byte page write buffer, and Schmitt-trigger inputs for noise immunity. It is used in embedded systems for parameter storage, calibration data retention, and configuration backup where low-voltage operation and long-term data integrity are critical.

For engineers reviewing the 24AA08H-I/MS datasheet, 24AA08H-I/MS pinout, 24AA08H-I/MS application, or 24AA08H-I/MS equivalent, key selection considerations include its 1.7V minimum supply, 400 kHz I²C clock support at V_CC ≥ 2.5V, 1 μA standby current, 3 ms typical page write time, and half-array hardware write-protect functionality - all validated for industrial-grade reliability and 200-year data retention.

Technical Context

The 24AA08H-I/MS implements a standard two-wire I²C slave interface with fixed 1010 control code and three block-select address bits (B2–B0), enabling access to four independent 256-word memory blocks. 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 V_CC, it disables writes to addresses 200h–3FFh while allowing full read access; tied to V_SS, full read/write operation is enabled. The device uses on-chip charge-pump circuitry for erase/write operations and includes V_CC threshold detection to inhibit programming below 1.5V.

Key Specifications

Pinout & Package

24AA08H-I/MS is supplied in an 8-lead MSOP (Micro Small Outline Package) with 0.65 mm lead pitch, 3.0 mm × 3.0 mm body, and exposed pad option (not electrically connected). Pin 1 is marked by a beveled corner or dot; orientation follows JEDEC MO-187.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC08BH-I/MS and AT24C08D-MAHM-T, the 24AA08H-I/MS uniquely supports 1.7V operation with full 400 kHz I²C speed above 2.5V and integrated hardware write-protect - making it the only choice for low-voltage industrial systems requiring both performance and memory partitioning security.

Availability

24AA08H-I/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, smart meter configuration storage, and medical device settings backup requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for 24AA08H-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 microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design, manufacturing, and sales operations.

The 24AA08H belongs to Microchip's serial EEPROM product line, engineered for reliable, low-power nonvolatile data storage in space-constrained industrial, medical, and consumer applications where extended temperature operation and long-term data integrity are essential.

FAQ

What is the minimum operating voltage for the 24AA08H-I/MS?

The 24AA08H-I/MS operates down to 1.7V, enabling direct use with single-cell lithium batteries or low-voltage microcontrollers. Below 1.7V, the internal V_CC detector disables write operations to prevent data corruption. This specification is validated across the full industrial temperature range (–40°C to +85°C) and applies specifically to the 24AA08H-I/MS variant - not the 24LC08BH series, which requires 2.5V minimum.

Does the 24AA08H-I/MS support 400 kHz I²C communication across its entire voltage range?

No - the 24AA08H-I/MS supports up to 400 kHz I²C clock frequency only when V_CC is 2.5V or higher. At 1.7V ≤ V_CC < 2.5V, maximum clock frequency is limited to 100 kHz per AC specifications in DS20002084B. This voltage-dependent timing behavior is inherent to the internal logic and must be accounted for in host controller configuration; the 24AA08H-I/MS does not auto-negotiate speed.

How does the hardware write-protect feature work on the 24AA08H-I/MS?

The WP pin on the 24AA08H-I/MS enables hardware-level protection of memory addresses 200h–3FFh (half the 8 Kbit array). When WP is tied to V_CC, write attempts to this region are ignored - reads remain fully functional. When WP is tied to V_SS, full read/write access is restored. This protection is active regardless of I²C command sequence and cannot be overridden in software.

Are the A0, A1, and A2 pins functional on the 24AA08H-I/MS?

No - the A0, A1, and A2 pins on the 24AA08H-I/MS are not internally connected and serve no functional purpose. They may be left floating or tied to V_SS/V_CC without affecting device operation. This differs from larger EEPROM families (e.g., 24AA1025) where these pins configure slave address; the 24AA08H-I/MS uses a fixed 1010xxx address with B2 as "don't care".

What is the page write time specification for the 24AA08H-I/MS?

The typical page write time for the 24AA08H-I/MS is 3 ms, with a maximum write cycle time (byte or page) of 5 ms per AC Characteristic TWC. This value is measured from the Stop condition that initiates the internal write cycle and includes erase, program, and verification phases. During this time, the device does not acknowledge I²C commands - a behavior leveraged in acknowledge polling for precise timing control.