24AA256-I/SM

Memory IC Overview

The Microchip Technology 24AA256-I/SM is a 256-Kbit (32K x 8) Serial Electrically Erasable PROM (EEPROM) utilizing an I²C-compatible two-wire serial interface. It operates across a supply voltage range of 1.7V to 5.5V with a maximum clock frequency of 400 kHz. The device supports page write operations up to 64 bytes and includes hardware write protection via the WP pin. It features Schmitt trigger inputs for noise suppression, output slope control to eliminate ground bounce, and ESD protection exceeding 4000V. The component is available in an 8-lead MSOP package and complies with RoHS standards.

Memory IC Feature Summary

• Low-power CMOS technology with active current of 400 µA maximum and standby current of 1 µA maximum.
• Hardware write-protect capability enabled by tying the WP pin to VCC.
• Supports cascading up to eight devices on the same bus using functional address lines A0, A1, and A2.
• Includes internal high-voltage generator and self-timed erase/write cycles.

Memory IC Applications

• Personal communications systems
• Data acquisition applications
• Industrial control systems requiring non-volatile data storage

Memory IC Procurement Notes

Verify that the ordering suffix 'I' corresponds to the Industrial temperature range (-40°C to +85°C). Confirm the 'SM' suffix indicates the 8-lead MSOP package type. Ensure compatibility with the system's I²C bus voltage levels, as the device supports operation down to 1.7V. Check for specific factory programming requirements if pre-programmed memory content is necessary for the application.

Memory IC Selection Notes

Select this part when a 256-Kbit EEPROM with low-voltage operation (down to 1.7V) is required. The 400 kHz clock speed is suitable for standard I²C buses. Consider the MSOP package for surface-mount applications needing a compact footprint. Note that the MSOP package has only one functional chip select pin (A2), limiting bus expansion to two devices compared to eight for other packages.

Memory IC Part Context

The 24AA256 is part of the 24XX256 family, which also includes the 24LC256 and 24FC256 variants. These devices share similar physical characteristics but differ in voltage ranges and clock speeds. The 24AA256 specifically supports the lowest voltage range starting at 1.7V, distinguishing it from the 24LC256 which requires a minimum of 2.5V.

Memory IC Replacement Considerations

Cross-reference with 24LC256-I/SM or 24FC256-I/SM for voltage or speed variations. Verify package compatibility and electrical specifications before substitution.