Microchip Technology AT24C02B-TH-B

Overview

AT24C02B-TH-B from Microchip Technology (formerly Atmel) is a 2 Kbit two-wire serial EEPROM organized as 256 × 8 bits, operating from 1.8 V to 5.5 V, featuring hardware write protection via the WP pin and Schmitt-trigger inputs for noise immunity. It supports up to 1 MHz I²C communication at 5 V and 400 kHz at 1.8 V, and is commonly used in industrial control systems for parameter storage and calibration data retention.

For engineers reviewing the AT24C02B-TH-B datasheet, AT24C02B-TH-B pinout, AT24C02B-TH-B application, or AT24C02B-TH-B equivalent, key selection considerations include its TSSOP-8 package with NiPdAu lead finish, 1 million write cycles endurance, 100-year data retention, page-write capability (8-byte pages), and compatibility with standard I²C bus timing requirements across voltage ranges.

Technical Context

The AT24C02B-TH-B implements a two-wire (I²C-compatible) serial interface with open-drain SDA and input-only SCL, supporting standard-mode (100 kHz), fast-mode (400 kHz), and fast-mode plus (1 MHz at 5 V) signaling. Device addressing uses three hard-wired A0–A2 pins, enabling up to eight devices on a single bus.

Internally, it features an 8-byte page buffer, self-timed write cycle (≤5 ms), and hardware write protection that disables all writes when WP is pulled high. Its memory array is partitioned into 32 pages of 8 bytes each, with automatic address incrementing during sequential reads and page-boundary rollover during page writes.

Key Specifications

Pinout & Package

AT24C02B-TH-B is supplied in an 8-lead Thin Shrink Small Outline Package (TSSOP), body size 4.4 mm × 3.0 mm, with NiPdAu lead finish and moisture sensitivity level (MSL) 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M24C02-RMN6TP and BR24G02NUX-10, the AT24C02B-TH-B provides hardware write protection and industrial-grade reliability at lower cost, while offering identical memory architecture and I²C timing - making it optimal for cost-sensitive industrial and consumer designs where WP functionality and standard temperature range suffice.

Availability

AT24C02B-TH-B is available at Aetrix Electronics and suitable for industrial control systems, consumer appliance manufacturing, medical device production, and automotive body electronics requiring stable component supply and long-term obsolescence support.

Supply support for AT24C02B-TH-B 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 is a global semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with broad industrial and automotive qualification capabilities.

The AT24C02B-TH-B belongs to Microchip's legacy serial EEPROM product line, designed specifically for low-power, space-constrained embedded systems needing reliable, byte-addressable nonvolatile storage with minimal external components.

FAQ

What is the maximum I²C clock frequency supported by the AT24C02B-TH-B?

The AT24C02B-TH-B supports up to 1 MHz I²C clock frequency when operated at VCC = 5.0 V, and 400 kHz at VCC = 1.8 V, 2.5 V, or 2.7 V. These values are specified in Table 2-3 of the official datasheet and reflect guaranteed AC timing performance under recommended operating conditions. The AT24C02B-TH-B does not support higher frequencies such as 3.4 MHz (Fast-mode Plus) or 5 MHz (Ultra Fast-mode).

Does the AT24C02B-TH-B require external pull-up resistors on SDA and SCL lines?

Yes, the AT24C02B-TH-B requires external pull-up resistors on both SDA and SCL lines because its SDA pin is open-drain and SCL is input-only. Typical values range from 1.8 kΩ (for 1 MHz at 5 V) to 10 kΩ (for 100 kHz at 1.8 V), selected based on bus capacitance and desired rise time. The AT24C02B-TH-B itself does not integrate pull-up circuitry.

How does the write protect (WP) pin function on the AT24C02B-TH-B?

When the WP pin of the AT24C02B-TH-B is driven high (tied to VCC), all write operations - including byte writes, page writes, and write-to-protect-register commands - are disabled. When WP is grounded, normal read/write operations proceed. This hardware-level protection operates independently of I²C commands and remains active during power-up sequences, ensuring data integrity before firmware initialization.

Can the AT24C02B-TH-B be used in automotive applications?

The AT24C02B-TH-B is qualified for industrial temperature range (–40 °C to +85 °C) and is not AEC-Q100 qualified. While it may function in some automotive cabin applications, Microchip explicitly states that "Atmel's products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life." For automotive body or infotainment systems requiring qualification, consider AEC-Q100-compliant alternatives like BR24G02NUX-10.

What package type and lead finish does the AT24C02B-TH-B use?

The AT24C02B-TH-B uses an 8-lead Thin Shrink Small Outline Package (TSSOP) with 4.4 mm body width and NiPdAu (Nickel-Palladium-Gold) lead finish. This finish provides superior wire-bondability, corrosion resistance, and solderability consistency, and is compliant with JEDEC MO-153 standards. The 'TH' in the part number explicitly denotes the TSSOP package variant.