Microchip Technology 24LC32AT-E/OT16KVAO

Overview

24LC32AT-E/OT16KVAO from Microchip Technology is a 32-Kbit I²C serial EEPROM organized as 4K × 8-bit memory with hardware write-protection, 32-byte page buffer, and operation from 2.5V to 5.5V. It supports 400 kHz clock frequency at V_CC ≥ 2.5V, delivers 1 µA standby current, and guarantees >1 million erase/write cycles with >200 years data retention. It is used in industrial sensor calibration storage and embedded system configuration backup.

For engineers reviewing the 24LC32AT-E/OT16KVAO datasheet, 24LC32AT-E/OT16KVAO pinout, 24LC32AT-E/OT16KVAO application, or 24LC32AT-E/OT16KVAO equivalent, key selection criteria include I²C bus compatibility at extended temperature (–40°C to +125°C), OT package footprint constraints, WP pin-controlled hardware write protection, and page-write timing under 5 ms.

Technical Context

The 24LC32AT-E/OT16KVAO implements a two-wire I²C interface with Schmitt-trigger inputs on SDA/SCL for noise immunity and slope-controlled outputs to suppress ground bounce. Its internal address pointer enables current-address, random, and sequential read modes, while the 32-byte page buffer allows burst writes within a single physical page boundary (0x000–0x01F, 0x020–0x03F, etc.).

Write protection is enforced via the WP pin: tied to V_CC, it inhibits all array writes but permits reads; sampling occurs at the Stop bit of each write command. Acknowledge polling is supported to detect write-cycle completion without fixed delays, improving bus utilization in time-critical systems.

Key Specifications

Pinout & Package

24LC32AT-E/OT16KVAO is packaged in an 8-lead OT (SOIJ) package - a 5.28 mm wide, gull-wing surface-mount outline with standard 1.27 mm pitch. The package includes exposed pad option (not electrically connected by default) and conforms to JEDEC MS-012AC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC32AT-E/OT16KVAO, the 24LC32AT-I/OT offers identical functionality at lower cost but excludes extended-temperature validation, while the AT24C32D-SSHM-T provides faster writes and wider voltage range but sacrifices automotive-grade reliability and endurance - making 24LC32AT-E/OT16KVAO optimal for mission-critical industrial and automotive deployments.

Availability

24LC32AT-E/OT16KVAO is available at Aetrix Electronics and suitable for industrial sensor calibration storage, automotive ECU configuration backup, and medical device settings retention requiring stable component supply across multi-year production cycles.

Supply support for 24LC32AT-E/OT16KVAO 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, serving industrial, automotive, and communications markets with vertically integrated silicon and development tools.

The 24LC32A product line delivers robust, low-power I²C EEPROMs optimized for configuration storage and calibration data retention in harsh-temperature embedded systems - emphasizing AEC-Q100 qualification, hardware write protection, and long-term data integrity.

FAQ

What is the maximum I²C clock frequency supported by the 24LC32AT-E/OT16KVAO?

The 24LC32AT-E/OT16KVAO supports up to 400 kHz I²C clock frequency when V_CC is 2.5V or higher. At voltages below 2.5V, the maximum clock rate drops to 100 kHz. This dual-speed capability ensures interoperability with legacy 100 kHz buses while enabling faster configuration updates in modern 3.3V systems. The 24LC32AT-E/OT16KVAO's AC timing parameters - including THIGH, TLOW, and TSU:DAT - are fully specified for both speed grades in the official Microchip datasheet DS20001713P.

Does the 24LC32AT-E/OT16KVAO require external pull-up resistors on SDA and SCL lines?

Yes, the 24LC32AT-E/OT16KVAO requires external pull-up resistors on both SDA and SCL lines because its I²C interface uses open-drain outputs. For 400 kHz operation, a 2 kΩ resistor to V_CC is recommended; for 100 kHz, 10 kΩ is typical. These values ensure proper rise times (TR ≤ 300 ns at 400 kHz) and noise margin while avoiding excessive bus capacitance loading. The 24LC32AT-E/OT16KVAO's internal Schmitt triggers tolerate slow edges but rely on external pull-ups to meet I²C specification voltage thresholds.

How does hardware write-protection work on the 24LC32AT-E/OT16KVAO?

Hardware write-protection on the 24LC32AT-E/OT16KVAO is controlled by the WP (Write-Protect) pin: when tied to V_CC, all write operations (byte and page) are inhibited, though read operations remain fully functional. The pin is sampled at the Stop bit of each write command, so toggling WP mid-cycle has no effect. This feature prevents accidental overwrites during power-up/down or firmware glitches. Unlike software lock bits, WP operates at the silicon level - ensuring immunity to corrupted MCU code or bus contention events affecting the 24LC32AT-E/OT16KVAO.

What package type does the 24LC32AT-E/OT16KVAO use, and what are its key mechanical dimensions?

The 24LC32AT-E/OT16KVAO uses the 8-lead SOIJ (Small Outline J-bend) package, also designated OT in Microchip's ordering nomenclature. Its body width is 5.28 mm, lead pitch is 1.27 mm, and overall length is 5.33 mm. The J-bend leads provide robust solder joint reliability in thermal cycling environments. This package matches industry-standard land patterns for SOIC-8 but with gull-wing geometry - enabling drop-in replacement in space-constrained designs where MSOP or DFN footprints are unavailable. The 24LC32AT-E/OT16KVAO's marking includes "24LC32A", "I/SM", and date code per DS20001713P-page 13.

Can multiple 24LC32AT-E/OT16KVAO devices share the same I²C bus, and how is addressing managed?

Yes, up to eight 24LC32AT-E/OT16KVAO devices can share one I²C bus using hardware address pins A0, A1, and A2. Each pin is hardwired to V_SS or V_CC to configure a unique 3-bit chip address, forming part of the 7-bit client address (1010 A2 A1 A0). This allows contiguous 256-Kbit expansion across devices. Addressing is strictly static - pins must be stable before the Start condition. The 24LC32AT-E/OT16KVAO does not support dynamic address assignment or software-configurable IDs, ensuring deterministic arbitration and eliminating address collision risks in multi-device systems.