Microchip Technology 24AA01H-I/P

Overview

24AA01H-I/P 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 (40h–7Fh). It serves in embedded system configuration storage, sensor calibration data retention, and power-fail-safe parameter backup.

For engineers reviewing the 24AA01H-I/P datasheet, 24AA01H-I/P pinout, 24AA01H-I/P application, or 24AA01H-I/P equivalent, key selection criteria include low-voltage operation down to 1.7V, 1 μA standby current, Schmitt-trigger noise immunity on SDA/SCL, page-write capability (up to 8 bytes), and half-array hardware write-protection via WP pin.

Technical Context

The 24AA01H-I/P implements a slave-only I²C interface with fixed 4-bit device code '1010' and three don't-care address bits, enabling single-device addressing without A0–A2 pin usage. Its internal architecture includes an 8-byte page buffer, address pointer auto-increment, and VCC threshold detector disabling write logic below 1.5V.

Write protection is implemented via the WP pin: tied to VSS enables full-array read/write; tied to VCC locks addresses 40h–7Fh against writes while permitting reads. All I/O pins feature Schmitt-trigger inputs and output slope control to suppress ground bounce and bus noise.

Key Specifications

Pinout & Package

24AA01H-I/P uses an 8-lead PDIP (Plastic Dual In-Line Package, 300 mil body) with through-hole mounting. Pin 1 is A0 (no internal connection); pins A1 and A2 are similarly unconnected. VSS (pin 4) and VCC (pin 8) provide power rails; SDA (pin 5) and SCL (pin 6) implement open-drain I²C signaling requiring external pull-ups; WP (pin 7) controls half-array write protection; all unused address pins may float or tie to VSS/VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA01H-I/P, 24LC01BH-I/P trades 1.7V compatibility for identical industrial-grade reliability, while AT24C01D-SSHM-T sacrifices hardware write-protection for broader vendor availability - making 24AA01H-I/P optimal for safety-critical, low-voltage, write-protected use cases.

Availability

24AA01H-I/P is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded system configuration, and power-fail safe logging requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for 24AA01H-I/P 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, mixed-signal, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA01H-I/P belongs to Microchip's 24XX01H family of I²C serial EEPROMs, designed specifically for ultra-low-voltage, high-reliability nonvolatile storage in space-constrained industrial and automotive subsystems.

FAQ

What is the minimum VCC voltage required for reliable operation of the 24AA01H-I/P?

The 24AA01H-I/P 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 logic to prevent corrupted data, and the device enters a safe read-only state. This 1.7V minimum enables direct interface with 1.8V microcontrollers and energy-harvesting power supplies without regulation overhead. The 24AA01H-I/P maintains full I²C timing compliance and 400 kHz clock capability at 1.7V.

How does the hardware write-protect function work on the 24AA01H-I/P?

The WP pin on the 24AA01H-I/P provides hardware-level write protection for memory addresses 40h–7Fh (half the array). When WP is tied to VCC, writes to that block are inhibited while reads remain fully functional; when WP is tied to VSS, full-array read/write access is enabled. This is implemented entirely in silicon with no firmware dependency, making it immune to software crashes or power glitches. The 24AA01H-I/P does not require any I²C commands to activate or configure this protection.

Can the 24AA01H-I/P be used in a system with multiple I²C devices sharing the same bus?

Yes, the 24AA01H-I/P supports standard I²C bus arbitration and can coexist with other I²C devices. Its fixed 4-bit device code '1010' and three don't-care address bits mean it responds only to control bytes starting with '1010xxx0' (write) or '1010xxx1' (read), regardless of A0–A2 pin states. Since those pins are unconnected internally, the 24AA01H-I/P occupies a single, fixed I²C address (0xA0 for write, 0xA1 for read), simplifying bus topology in single-device configurations but requiring address conflict checks in multi-EEPROM systems.

What is the maximum write cycle time for a full page on the 24AA01H-I/P?

The 24AA01H-I/P has a typical page write time of 3 ms and a maximum write cycle time of 5 ms per byte or page, as specified in AC Characteristics Table 1-2 (Parameter TWC). This applies to both single-byte and up to 8-byte page writes. During this internal write cycle, the device does not acknowledge I²C commands (ACK polling is supported to detect completion), ensuring data integrity. The 5 ms worst-case value accounts for process/voltage/temperature extremes across the industrial grade.

Is the 24AA01H-I/P RoHS compliant and lead-free?

Yes, the 24AA01H-I/P is Pb-free and RoHS compliant, as explicitly stated in the device features list and packaging information section of the DS22104A datasheet. The PDIP package uses matte tin (Sn) plating per JEDEC standards, and marking includes the Pb-free JEDEC designator where physically possible. Microchip confirms full compliance with Directive 2011/65/EU, and the 24AA01H-I/P carries appropriate labeling on reels and shipping cartons per regulatory requirements.