Microchip Technology 24C01C-I/ST

Overview

24C01C-I/ST from Microchip Technology is a 1 Kbit (128 × 8) I²C-compatible serial EEPROM operating from 4.5V to 5.5V, featuring 16-byte page write buffer, 1 ms max write cycle time, and industrial temperature range (–40°C to +85°C). It supports up to eight devices on one bus via A0–A2 address pins and delivers ultra-low standby current (5 µA max) for power-sensitive embedded systems.

For engineers reviewing the 24C01C-I/ST datasheet, 24C01C-I/ST pinout, 24C01C-I/ST application, or 24C01C-I/ST equivalent, key selection criteria include I²C clock compatibility (100 kHz / 400 kHz), Schmitt-trigger noise immunity on SDA/SCL, WP pin write protection, cascading capability, and verified 1M+ endurance cycles with >200-year data retention.

Technical Context

The 24C01C-I/ST implements a true 2-wire I²C slave interface with open-drain SDA/SCL requiring external pull-ups, internal address pointer auto-increment for sequential reads, and hardware-based write-cycle timing that eliminates need for external delay. Its memory array is organized as a single 128-word block with page boundaries aligned to 16-byte offsets.

It integrates Schmitt-trigger inputs and input filtering (50 ns spike suppression) on SDA/SCL, VCC threshold detection (<3.8 V disable), and output slope control to suppress ground bounce-enabling reliable operation in electrically noisy industrial environments without additional signal conditioning.

Key Specifications

Pinout & Package

24C01C-I/ST is supplied in 6-lead SOT-23 package (3.0 mm × 1.7 mm × 1.1 mm), with pin 1 marked by laser dot. This compact surface-mount package supports high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C01D-SSHM-T and BR24G01FJ-WE2, the 24C01C-I/ST offers proven industrial temperature reliability at fixed 4.5V–5.5V operation, making it optimal for legacy 5V systems where voltage headroom and qualification depth outweigh low-voltage flexibility.

Availability

24C01C-I/ST is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device serialization, consumer remote control memory, and automotive body control module settings requiring stable component supply and long-term lifecycle continuity.

Supply support for 24C01C-I/ST 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, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24C01C belongs to Microchip's legacy serial EEPROM product line, designed specifically for cost-sensitive, space-constrained embedded systems requiring reliable nonvolatile storage with minimal external components and robust I²C interoperability.

FAQ

What is the maximum I²C clock frequency supported by the 24C01C-I/ST?

The 24C01C-I/ST supports I²C clock frequencies up to 400 kHz under industrial temperature conditions (–40°C to +85°C). At 100 kHz, timing margins increase significantly, allowing longer trace lengths or higher bus capacitance. The device does not support standard-mode Fast-mode Plus (1 MHz) or High-speed mode.

Does the 24C01C-I/ST have a write-protect pin, and how is it implemented?

Yes, the 24C01C-I/ST supports hardware write protection via the WP (Write Protect) pin. When WP is driven low, all write operations-including byte, page, and address pointer updates-are inhibited. When WP is high or floating, normal write functionality is enabled. This pin is not present in the SOT-23 package variant of the 24C01C-I/ST.

How many 24C01C-I/ST devices can be connected on the same I²C bus?

Up to four 24C01C-I/ST devices in SOT-23 package can share one I²C bus, using combinations of A0 and A1 address pins (A2 is not available in this package). Each device must have a unique 2-bit chip address (00, 01, 10, or 11) hardwired to VSS or VCC to avoid address collisions.

What is the page write boundary for the 24C01C-I/ST, and why does it matter?

The 24C01C-I/ST has a 16-byte page write boundary, meaning valid page writes must start at addresses divisible by 16 (e.g., 0x00, 0x10, 0x20). Crossing a boundary causes wraparound within the same page-not continuation into the next. This constraint requires firmware to split multi-page writes manually, or risk overwriting earlier bytes in the current page.

Is the 24C01C-I/ST RoHS compliant and lead-free?

Yes, the 24C01C-I/ST is Pb-free and RoHS compliant per Microchip's DS21201K documentation. It uses matte tin (Sn) plating per JEDEC J-STD-609, and the "ST" suffix denotes the SOT-23 package with lead-free finish. Full compliance documentation is available in Microchip's Pb-free packaging specification.