Microchip Technology 24AA02HT-I/MS

Overview

24AA02HT-I/MS from Microchip Technology Inc. is a 2 Kbit I²C-compatible serial EEPROM organized as 256 × 8-bit memory with half-array hardware write-protection (addresses 0x80–0xFF), 1.7V–5.5V operation, and industrial temperature range (−40°C to +85°C) in an 8-lead MSOP package. It supports up to 400 kHz clock frequency, features Schmitt-trigger inputs, slope-controlled outputs, and 8-byte page write buffer for embedded system configuration storage.

For engineers reviewing the 24AA02HT-I/MS datasheet, 24AA02HT-I/MS pinout, 24AA02HT-I/MS application, or 24AA02HT-I/MS equivalent, key selection criteria include low-voltage operation down to 1.7V, hardware write-protect capability, I²C bus noise immunity via Schmitt triggers, endurance of >1 million erase/write cycles, and compatibility with standard 2-wire serial protocols in space-constrained industrial designs.

Technical Context

The 24AA02HT-I/MS implements a two-wire I²C interface with fixed 7-bit client address (1010xxxR/W), where A0–A2 pins are unconnected and may be left floating or tied to VSS/VCC. Its internal architecture includes a page buffer, address pointer, EEPROM array with X/Y decoding, and dedicated control logic for self-timed byte/page writes.

Write protection is implemented via the WP pin: when tied to VCC, addresses 0x80–0xFF are write-inhibited while reads remain fully functional; when tied to VSS, full array access is enabled. Acknowledge polling is supported to detect write cycle completion without fixed timing delays.

Key Specifications

Pinout & Package

8-lead MSOP (Micro Small Outline Package) with 0.65 mm pitch, 3.0 mm × 3.0 mm body, and exposed pad optionally connected to VSS. Pin 1 marked by notch or dot; pin numbering follows standard MSOP convention (counterclockwise from mark).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC02BHT-I/MS and AT24C02D-SSHM-T, the 24AA02HT-I/MS uniquely supports 1.7V operation and offers true hardware-based half-array write protection independent of software state - making it optimal for battery-sensitive and safety-critical applications where guaranteed data integrity is mandatory.

Availability

24AA02HT-I/MS is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, and automotive body electronics requiring stable component supply, long-term data retention, and hardware-enforced write protection.

Supply support for 24AA02HT-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 24AA02H family was designed specifically for reliable, low-voltage, I²C-based nonvolatile storage in space-constrained embedded systems - emphasizing robustness, ease of integration, and long-term data integrity in industrial and automotive environments.

FAQ

What is the operating voltage range of the 24AA02HT-I/MS?

The 24AA02HT-I/MS operates from 1.7V to 5.5V, enabling use in ultra-low-power applications such as coin-cell-powered sensors and energy-harvesting systems. This wide range accommodates both 1.8V logic domains and legacy 5V systems without level translation. The device maintains full I²C functionality-including 400 kHz operation-across this entire voltage span, as confirmed in the DS20002105B datasheet Section 1.0.

How does the hardware write-protection work on the 24AA02HT-I/MS?

The 24AA02HT-I/MS uses the WP pin to enable hardware write-protection: when WP is tied to VCC, addresses 0x80–0xFF are write-inhibited while reads remain fully accessible; when WP is tied to VSS, full array write access is enabled. This protection is active immediately at power-on and requires no software initialization, ensuring critical configuration data remains immutable even during firmware faults or unexpected resets.

Is the 24AA02HT-I/MS compatible with standard I²C bus speeds?

Yes, the 24AA02HT-I/MS supports standard-mode (100 kHz) and fast-mode (400 kHz) I²C operation. At VCC ≥ 2.5V, it achieves full 400 kHz performance with defined timing margins (e.g., THIGH ≥ 600 ns, TLOW ≥ 1300 ns). At 1.7V ≤ VCC < 2.5V, it defaults to 100 kHz mode to ensure reliable timing compliance - a behavior explicitly documented in Table 1-2 of the DS20002105B datasheet.

What is the endurance and data retention specification for the 24AA02HT-I/MS?

The 24AA02HT-I/MS guarantees more than 1,000,000 erase/write cycles and greater than 200 years of data retention at +25°C. These values are characterized and ensured per Microchip's qualification standards (not just typical), and apply across the full industrial temperature range (−40°C to +85°C). Endurance testing is performed under worst-case conditions (VCC = 5.5V, TA = 25°C), as stated in Table 1-2 Note 4.

Are the A0, A1, and A2 pins functional on the 24AA02HT-I/MS?

No - the A0, A1, and A2 pins on the 24AA02HT-I/MS are not internally connected and serve no functional purpose. As confirmed in Section 2.1 and Table 2-1 of DS20002105B, these pins may be left floating or tied to VSS or VCC without affecting device operation, addressing, or I²C communication. The device uses a fixed 7-bit slave address (1010xxx) where the "xxx" bits are don't-care, eliminating address selection requirements.