Microchip Technology AT24C512B-TH-B

Overview

AT24C512B-TH-B from Microchip Technology (formerly Atmel) is a 512 Kbit (65,536 × 8) two-wire serial EEPROM with 1.8V operation (1.8V–3.6V), 128-byte page write capability, hardware write protection via WP pin, and 400 kHz I²C bus compatibility at 1.8V. It is used for nonvolatile parameter storage in embedded controllers, industrial sensors, and power management systems requiring low-voltage, high-reliability memory.

For engineers reviewing the AT24C512B-TH-B datasheet, AT24C512B-TH-B pinout, AT24C512B-TH-B application, or AT24C512B-TH-B equivalent, key selection criteria include voltage range (1.8V–3.6V), TSSOP-8 package footprint, 128-byte page write mode, 1,000,000 write endurance, and hardware write protect functionality.

Technical Context

The AT24C512B-TH-B implements a standard two-wire (I²C-compatible) interface with Schmitt-triggered, noise-filtered SDA/SCL inputs and bidirectional data transfer protocol. Its internal architecture supports cascading up to eight devices on a single bus using three hardware address pins (A0–A2).

It features a self-timed write cycle (max 5 ms), 16-bit word addressing, and a dedicated Write Protect (WP) pin that disables all writes when pulled high. The device operates across –40°C to +85°C and supports both byte and page write modes with acknowledge polling for write completion detection.

Key Specifications

Pinout & Package

AT24C512B-TH-B is supplied in an 8-lead Thin Shrink Small Outline Package (TSSOP) with 4.4 mm body width, 0.65 mm lead pitch, and NiPdAu lead finish. Pin 1 is marked by a dot in the top-left corner of the package.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C512BN-SH-B and M24C512-RMN6TP, the AT24C512B-TH-B delivers optimal board-area efficiency in TSSOP-8 while maintaining full compatibility with 1.8V I²C masters and offering proven 40-year data retention - making it ideal for compact, long-life industrial electronics.

Availability

AT24C512B-TH-B is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded controller configuration, and power management unit (PMU) applications requiring stable component supply, long-term data retention, and low-voltage I²C compatibility.

Supply support for AT24C512B-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 acquired Atmel in 2016 and now manufactures, supports, and qualifies the AT24C512B-TH-B as part of its broad serial EEPROM portfolio.

The AT24C512B family was designed for robust, low-power nonvolatile storage in resource-constrained embedded systems - emphasizing reliability, noise immunity, and seamless I²C integration across industrial, medical, and communications equipment.

FAQ

What is the operating voltage range for the AT24C512B-TH-B?

The AT24C512B-TH-B operates from 1.8V to 3.6V, supporting low-power systems such as battery-operated sensors and portable medical devices. This 1.8V variant is distinct from the 2.5V version (e.g., AT24C512B-TH25-B) and must not be substituted without verifying system rail compatibility. The AT24C512B-TH-B is not rated for 5V operation.

Does the AT24C512B-TH-B support page write operations, and what is the maximum size?

Yes, the AT24C512B-TH-B supports 128-byte page write operations, allowing up to 128 sequential bytes to be written in a single I²C transaction. This reduces firmware overhead and improves write efficiency compared to byte-by-byte writes. Partial page writes are permitted, and address roll-over occurs only within the same 128-byte page boundary. The AT24C512B-TH-B enforces this limit strictly per its internal page counter.

How does the Write Protect (WP) pin function on the AT24C512B-TH-B?

The WP pin on the AT24C512B-TH-B is an active-high hardware lock: when pulled to VCC, all write operations (byte, page, and write-enable commands) are inhibited, preserving memory contents even during firmware errors or power transients. When grounded, normal write functionality is enabled. The AT24C512B-TH-B includes internal pull-downs, but Atmel recommends hardwiring WP to a defined state to prevent noise-induced glitches.

What package type is used for the AT24C512B-TH-B, and what are its key mechanical dimensions?

The AT24C512B-TH-B uses an 8-lead TSSOP package (JEDEC MO-153, variation AA) with a 4.4 mm body width, 6.4 mm length, and 0.65 mm lead pitch. Its height is ≤1.20 mm, making it suitable for slim-profile consumer and industrial assemblies. The NiPdAu lead finish ensures solderability and corrosion resistance. Pin 1 is marked by a dot in the top-left corner of the package outline.

Can multiple AT24C512B-TH-B devices share the same I²C bus, and how is addressing managed?

Yes, up to eight AT24C512B-TH-B devices can share a single I²C bus using hardware address pins A0, A1, and A2. Each pin can be tied to GND or VCC to generate a unique 3-bit device address, resulting in eight possible slave addresses (1010000x to 1010111x). The AT24C512B-TH-B ignores transactions with mismatched addresses, enabling selective communication without software arbitration.