Microchip Technology 24LC1025-I/P

Overview

24LC1025-I/P from Microchip Technology Inc. is a 128K × 8 (1024 kbit) I²C-compatible serial EEPROM with industrial temperature range (–40°C to +85°C), 2.5V–5.5V supply voltage, and 400 kHz max clock frequency. It features 128-byte page write buffer, hardware write-protection via WP pin, and Schmitt-trigger inputs for noise immunity. Used in embedded systems for nonvolatile parameter storage, calibration data retention, and firmware configuration.

For engineers reviewing the 24LC1025-I/P datasheet, 24LC1025-I/P pinout, 24LC1025-I/P application, or 24LC1025-I/P equivalent, key selection criteria include VCC operating range (2.5–5.5 V), I²C bus compatibility up to 400 kHz, page write time (3 ms typical), endurance (1 million cycles), and data retention (>200 years).

Technical Context

The 24LC1025-I/P implements a two-wire I²C interface with slave-only operation, supporting standard-mode (100 kHz) and fast-mode (400 kHz) timing per JEDEC JESD36. Its internal architecture includes dual 512 kbit memory blocks accessed via block-select bit B₀, enabling contiguous addressing across up to four devices on one bus.

It uses an on-chip high-voltage generator for EEPROM programming, self-timed erase/write cycles, and automatic address pointer increment during sequential reads. The A2 pin is hardwired to VCC for device enable, while A0/A1 provide user-configurable chip select for multi-device cascading.

Key Specifications

Pinout & Package

24LC1025-I/P is packaged in an 8-lead PDIP (Plastic Dual In-line Package) with 300-mil body width, RoHS-compliant matte tin lead finish, and industrial-grade thermal rating (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA1025-I/P and AT24C1024-10PU-2.7, the 24LC1025-I/P provides optimal balance of industrial temperature support, strict A2-enforced activation, and proven interoperability with legacy Microchip-based designs - making it preferred for long-lifecycle industrial and automotive deployments.

Availability

24LC1025-I/P is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, and automotive body control modules requiring stable component supply, long-term data integrity, and RoHS-compliant packaging.

Supply support for 24LC1025-I/P 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 microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC1025-I/P belongs to Microchip's 24XX1025 family of I²C serial EEPROMs, designed specifically for robust, low-power nonvolatile storage in industrial, automotive, and medical applications demanding high reliability and extended data retention.

FAQ

What is the maximum I²C clock frequency supported by the 24LC1025-I/P?

The 24LC1025-I/P supports up to 400 kHz I²C clock frequency when VCC is 2.5 V or higher. At VCC < 2.5 V, maximum clock drops to 100 kHz. This dual-speed capability ensures compatibility with both legacy 100 kHz systems and modern fast-mode controllers - a key advantage over fixed-speed EEPROMs. The 24LC1025-I/P automatically adapts timing based on supply voltage without external configuration.

How does the A2 pin function on the 24LC1025-I/P, and what happens if it is not tied to VCC?

The A2 pin on the 24LC1025-I/P is a non-configurable chip select that must be hard-wired to VCC for proper device operation. If left floating or connected to VSS, the 24LC1025-I/P will not respond to I²C commands - resulting in communication failure. This design prevents accidental activation in multi-device buses and enforces explicit hardware enable, improving system-level reliability. Always verify A2 = VCC during PCB layout and bring-up.

Can the 24LC1025-I/P perform sequential reads across its full 1024 kbit memory space?

No - sequential reads on the 24LC1025-I/P are limited to 512 kbit blocks (00000h–0FFFFh and 10000h–1FFFFh) due to internal addressing architecture. To read the entire memory, software must issue separate read commands with appropriate B₀ bit setting for each block. This boundary is enforced by hardware and cannot be overridden. The 24LC1025-I/P will auto-roll address pointers within each block but never across the 512 kbit boundary.

What is the purpose of the WP pin on the 24LC1025-I/P, and how does it affect write operations?

The WP (Write-Protect) pin on the 24LC1025-I/P provides hardware-level write inhibition: when tied to VCC, all write operations (byte and page) are blocked while read access remains fully functional. The pin is sampled at the Stop condition of each write command - toggling WP mid-cycle has no effect. This feature protects critical calibration or security data from corruption during power transitions or firmware faults, and is more reliable than software-only locking mechanisms used in the 24LC1025-I/P.

Does the 24LC1025-I/P require an external high-voltage programming supply?

No - the 24LC1025-I/P integrates an on-chip charge pump (HV generator) that derives the required programming voltage from the standard VCC supply (2.5–5.5 V). This eliminates need for external VPP pins, dedicated programming voltages, or complex power sequencing. All erase and write operations are fully self-contained within the 24LC1025-I/P, simplifying system design and reducing BOM count compared to older EEPROM architectures.