25AA640A-I/MS

Memory IC Overview

The Microchip Technology 25AA640A-I/MS is a 64-Kbit (8192 x 8-bit) Serial Electrically Erasable PROM accessed via an SPI-compatible bus. It operates within a voltage range of 1.8V to 5.5V and supports a maximum clock frequency of 10 MHz at higher voltages. The device features a 32-byte page size, self-timed write cycles up to 5 ms, and industrial temperature ratings from -40°C to +85°C. It includes block write protection, power-on data protection, and high reliability with over 1 million erase/write cycles and greater than 200 years of data retention.

Memory IC Feature Summary

• Supports serial communication through standard SPI signals including clock, data in, data out, and chip select inputs.
• Includes hardware write-protect functionality controlled by the WP pin and STATUS register bits for array security.
• Features a HOLD input that allows suspension of serial sequences without resetting the internal address pointer.

Memory IC Applications

• Data storage for configuration parameters in microcontroller systems
• Logging operational data in embedded devices
• Storing calibration values or user settings in consumer electronics

Memory IC Procurement Notes

Verify the specific suffix 'I' confirms the Industrial temperature range (-40°C to +85°C) and 'MS' denotes the MSOP package. Confirm RoHS compliance status as required by your assembly specifications. Ensure the design accounts for the 1.8V minimum supply voltage if operating in low-power environments. Check for any recent Product Change Notices regarding packaging or material updates.

Memory IC Selection Notes

Select this component when a non-volatile memory solution requires SPI interface compatibility with low pin count. The 64-Kbit capacity suits applications needing moderate storage for small datasets. Consider the MSOP package for space-constrained surface-mount designs. Verify that the system voltage remains within the 1.8V to 5.5V range to ensure proper operation across all specified conditions.

Memory IC Part Context

This part belongs to the 25XX640A family of 64-Kbit Serial EEPROMs manufactured by Microchip Technology. It shares functional similarities with the 25LC640A but differs in supply voltage requirements. The family utilizes a common instruction set and pinout across various packages such as SOIC, TSSOP, and DFN, allowing for flexible layout options while maintaining consistent software compatibility.

Memory IC Replacement Considerations

The 25LC640A serves as a direct functional substitute within the same family, though it requires a minimum supply voltage of 2.5V compared to the 25AA640A's 1.8V. Other 64-Kbit SPI EEPROMs from different manufacturers may require firmware adjustments due to differing command sets or timing characteristics.