Microchip 24LC21AT/SN 128K I²C Serial EEPROM for Low-Voltage System Design

The increasing demand for portable and battery-powered electronic devices has driven the need for low-voltage, non-volatile memory solutions that offer high reliability and minimal power consumption. The Microchip 24LC21AT/SN stands out as a robust 128K I²C serial EEPROM specifically engineered to meet these stringent requirements. Designed for low-voltage system applications, this memory IC integrates seamlessly into designs where power efficiency, compact form factor, and data integrity are paramount.

Operating at voltages as low as 1.7V, the 24LC21AT/SN is ideal for modern microcontrollers and systems powered by single-cell lithium batteries or other low-voltage sources. Its wide voltage range (1.7V to 5.5V) ensures compatibility with a variety of logic levels, making it versatile for use across multiple platforms. The device supports the ubiquitous I²C (Inter-Integrated Circuit) protocol, enabling communication with just two bidirectional lines: SDA (Serial Data) and SCL (Serial Clock). This simplifies PCB layout and reduces the number of GPIO pins required on the host microcontroller, which is crucial for space-constrained designs.

With a capacity of 128 kilobits (organized as 256 x 8 bits), the 24LC21AT/SN provides ample storage for system parameters, calibration data, user settings, and event logging. It features a 16-byte page write buffer, allowing for efficient data transfers and reducing write cycle times. The EEPROM also includes hardware write-protection via a dedicated WP (Write Protect) pin. When asserted, this pin prevents any write operations, safeguarding critical data from accidental corruption.

Another key advantage is its low power consumption. The device draws just 1 mA during active write operations and 1 μA in standby mode, making it suitable for always-on applications where power preservation is essential. Additionally, it supports partial page writes and boasts a endurance of 1 million write cycles per sector, coupled with a data retention period of over 200 years, ensuring long-term reliability.

The 24LC21AT/SN is available in an 8-lead SOIC package, which is both compact and easy to solder, facilitating high-volume manufacturing. Its extended temperature range (-40°C to +125°C) allows deployment in industrial and automotive environments where thermal conditions can be extreme.

ICGOODFIND: The Microchip 24LC21AT/SN is an excellent choice for designers seeking a reliable, low-voltage EEPROM solution. Its combination of wide voltage operation, I²C interface, hardware write-protection, and ultra-low power consumption makes it particularly well-suited for portable medical devices, IoT sensors, smart meters, and other battery-powered systems.

Keywords: Low-Voltage Operation, I²C Interface, Hardware Write-Protection, Ultra-Low Power Consumption, Serial EEPROM.