Microchip Technology AT24C512B-PU25

Overview

AT24C512B-PU25 from Microchip Technology (formerly Atmel) is a 512 Kbit (65,536 × 8) two-wire serial EEPROM optimized for low-power industrial and commercial systems. It operates across 2.5V to 5.5V supply, supports up to 1 MHz I²C clock at 2.5V/5.5V, features hardware write protection via WP pin, and delivers 1,000,000 write cycles with 40-year data retention - deployed in embedded controllers, power management units, and sensor calibration storage.

For engineers reviewing the AT24C512B-PU25 datasheet, AT24C512B-PU25 pinout, AT24C512B-PU25 application, or AT24C512B-PU25 equivalent, key selection criteria include voltage range compatibility (2.5V–5.5V), 128-byte page write capability, Schmitt-triggered noise-immune inputs, cascading support for up to eight devices on one bus, and PDIP-8 packaging with industrial temperature rating (–40°C to +85°C).

Technical Context

The AT24C512B-PU25 implements a standard two-wire (I²C-compatible) interface with open-drain SDA and edge-triggered SCL, supporting both byte and 128-byte page writes. Its internal address counter enables current-address and random-address read modes, while acknowledge polling allows host synchronization during self-timed 5 ms write cycles.

Device addressing uses three hardwired A2/A1/A0 pins to select among up to eight devices on a shared bus; the WP pin provides hardware-level memory lock when tied to VCC. All logic inputs feature Schmitt triggers and input filtering for robust operation in electrically noisy environments.

Key Specifications

Pinout & Package

AT24C512B-PU25 is supplied in an 8-lead PDIP (Plastic Dual In-line Package), 0.300" wide body (package code 8P3), with pin 1 identified by a notch or dot. This through-hole package supports manual prototyping, socket-based testing, and legacy board designs requiring mechanical robustness and thermal margin.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C512B-PU25, AT24C512BN-SH25-T trades PDIP flexibility for SMT scalability, while M24512-RDW6TP/K offers equivalent density and speed but omits multi-device addressing - making AT24C512B-PU25 uniquely suited for modular, multi-node industrial systems requiring scalable I²C topology.

Availability

AT24C512B-PU25 is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded controller configuration, and power supply firmware storage requiring stable component supply across extended product lifecycles.

Supply support for AT24C512B-PU25 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 maintains full technical and manufacturing continuity for the AT24Cxx EEPROM family. The company specializes in secure, reliable microcontrollers and memory solutions for industrial, automotive, and IoT markets.

The AT24C512B belongs to Microchip's serial EEPROM product line, engineered for robust nonvolatile data storage in resource-constrained embedded systems where low-voltage operation, long endurance, and I²C simplicity are essential.

FAQ

What voltage range does the AT24C512B-PU25 support?

The AT24C512B-PU25 supports a supply voltage range of 2.5V to 5.5V, enabling direct interfacing with both 3.3V and 5V microcontroller I/O domains. This dual-range capability eliminates the need for level-shifting circuitry in mixed-voltage systems and ensures compatibility with legacy 5V designs and modern low-power 3.3V platforms. The AT24C512B-PU25 is not rated for 1.8V operation - that variant is designated AT24C512B-PU.

Does the AT24C512B-PU25 support multi-device I²C bus configurations?

Yes, the AT24C512B-PU25 supports cascading up to eight devices on a single I²C bus using its three hardware address pins (A0, A1, A2). Each pin can be tied to VCC or GND to configure a unique 3-bit device address, allowing differentiated communication without software arbitration. This capability is intrinsic to the AT24C512B-PU25 silicon and documented in its device addressing section.

What is the maximum I²C clock frequency supported by the AT24C512B-PU25?

The AT24C512B-PU25 supports up to 1 MHz I²C clock frequency when operated at 2.5V or 5.5V supply. At lower voltages within its specified range, timing margins reduce accordingly - the 1 MHz rating is validated under 2.5V–5.5V conditions per Table 2-3 in the official datasheet. This enables faster configuration writes compared to standard 400 kHz EEPROMs, improving system boot and update performance.

How does the write protect (WP) pin function on the AT24C512B-PU25?

The WP pin on the AT24C512B-PU25 provides hardware-level write inhibition: when pulled high to VCC, all write operations (byte, page, and erase) are blocked regardless of software commands. When grounded, full read/write access is enabled. Internal weak pull-down ensures safe default behavior if left unconnected, though Microchip recommends explicit termination to avoid noise-induced glitches. This feature is integral to the AT24C512B-PU25's data integrity architecture.

Is the AT24C512B-PU25 available in surface-mount packages?

No - the AT24C512B-PU25 is specified exclusively in 8-lead PDIP (8P3) packaging per the ordering information table. Other variants like AT24C512BN-SH25-T offer SOIC, TSSOP, or dBGA2 packages, but the "-PU25" suffix denotes bulk-packaged PDIP only. This makes the AT24C512B-PU25 ideal for through-hole prototyping, socket-based validation, and legacy board replacements where lead spacing and mechanical stability are prioritized.