Microchip Technology AT24C128-10PU-1.8

Overview

AT24C128-10PU-1.8 from Microchip Technology (formerly Atmel) is a 128 Kbit (16,384 × 8) two-wire serial EEPROM optimized for low-voltage embedded systems. It operates from 1.8 V to 3.6 V, supports 100 kHz I²C bus speed at 1.8 V, features hardware write protection via the WP pin, and delivers 1 million write cycles with 40-year data retention. It is used in industrial sensor calibration storage and power meter firmware parameter backup.

For engineers reviewing the AT24C128-10PU-1.8 datasheet, AT24C128-10PU-1.8 pinout, AT24C128-10PU-1.8 application, or AT24C128-10PU-1.8 equivalent, key selection considerations include 1.8 V supply compatibility, 64-byte page write capability, Schmitt-triggered noise-immune inputs, and 8-lead PDIP package with lead-free/RoHS-compliant construction.

Technical Context

The AT24C128-10PU-1.8 implements a standard two-wire (I²C-compatible) serial interface with open-drain SDA and edge-triggered SCL, supporting up to four devices on a shared bus via A0/A1 address pins. Its internal architecture organizes memory as 256 pages of 64 bytes each, enabling partial-page writes without rollover within the same page boundary.

It uses an internally biased address and write-protect input circuitry that pulls A0, A1, and WP low when floating-provided board coupling capacitance remains below 3 pF-enabling simplified hardware design while maintaining deterministic behavior under noise or layout variation.

Key Specifications

Pinout & Package

AT24C128-10PU-1.8 is housed in an 8-lead JEDEC PDIP (8P3) package, 0.300" wide body, with RoHS-compliant green finish ("U" suffix). Pin 1 is bottom-left corner when viewing top-side marking; pin numbering follows standard DIP convention (counterclockwise from pin 1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C128-10PU-1.8, AT24C128B-SSHM-T offers extended temperature support and SOIC packaging for automated assembly, while M24C128-WMN6TP provides second-source flexibility with minor I²C address and pinout differences-both require layout or firmware review before substitution.

Availability

AT24C128-10PU-1.8 is available at Aetrix Electronics and suitable for industrial sensor calibration, smart energy metering, and PLC I/O module configuration requiring stable component supply and long-lifecycle support.

Supply support for AT24C128-10PU-1.8 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 nonvolatile memory solutions for industrial, automotive, and consumer applications.

The AT24C128 series was designed for reliable, low-voltage parameter storage in resource-constrained embedded systems-emphasizing noise immunity, write endurance, and seamless I²C integration with 8-bit and 32-bit MCUs.

FAQ

What is the maximum I²C clock frequency supported by AT24C128-10PU-1.8 at 1.8 V?

The AT24C128-10PU-1.8 supports a maximum I²C clock frequency of 100 kHz when operating at 1.8 V, as specified in Table 4 of its datasheet. This limit ensures robust timing margins under low-voltage conditions and accounts for increased rise/fall times and reduced drive strength. Exceeding this frequency may result in failed ACKs or data corruption during read/write sequences.

Does AT24C128-10PU-1.8 support page write operations, and what is the page size?

Yes, AT24C128-10PU-1.8 supports 64-byte page write operations. The device organizes its 16,384-byte memory into 256 pages of 64 bytes each. During a page write, up to 64 sequential bytes can be written in a single I²C transaction, with automatic internal address incrementation-reducing host overhead and bus occupancy compared to byte-by-byte writes.

How does the Write Protect (WP) pin function on AT24C128-10PU-1.8?

On AT24C128-10PU-1.8, the WP pin disables all write operations-including byte, page, and write-enable commands-when held high at VCC. When pulled low or left floating (with board coupling <3 pF), writes are enabled. This hardware-level protection operates independently of software state, providing critical safeguard against accidental or malicious memory corruption during power transients or firmware faults.

Is AT24C128-10PU-1.8 compatible with standard I²C protocols and controllers?

Yes, AT24C128-10PU-1.8 implements a standard two-wire serial interface fully compliant with I²C protocol specifications, including START/STOP conditions, 7-bit device addressing (with A0/A1 extension), ACK/NACK handshaking, and clock stretching. It interfaces directly with any I²C master-such as STM32, PIC, or ESP32 microcontrollers-without protocol translation or additional logic.

What is the endurance and data retention specification for AT24C128-10PU-1.8?

AT24C128-10PU-1.8 guarantees 1,000,000 write cycles and 40 years of data retention at +25°C. These values are validated for the "B" process version (not applicable to original AT24C128), and the -10PU-1.8 variant meets these specs per datasheet revision 0670T. Retention degrades logarithmically with temperature; at +85°C, expected retention exceeds 10 years.