25AA640AT-I/ST

Memory IC Overview

The Microchip Technology 25AA640AT-I/ST is a 64-Kbit (8192 x 8-bit) Serial Electrically Erasable PROM accessed via an SPI-compatible bus. It operates within a supply 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 with a maximum duration of 5 ms, and industrial temperature ratings from -40°C to +85°C. It utilizes an 8-lead TSSOP package.

Memory IC Feature Summary

• Supports high-speed serial communication with a maximum clock frequency of 10 MHz
• Includes hardware write protection mechanisms such as block protection and power-on data protection
• Features a hold pin to suspend transmission without resetting the serial sequence
• Complies with automotive AEC-Q100 qualification standards

Memory IC Applications

• Microcontroller system data storage
• Configuration parameter retention
• Automotive electronic modules
• Industrial control systems

Memory IC Procurement Notes

Verify that the ordering suffix 'T' corresponds to tape and reel packaging rather than tube or cut tape formats. Confirm the 'I' suffix indicates the Industrial temperature range (-40°C to +85°C). Ensure the 'ST' suffix matches the required 8-lead TSSOP package type for your PCB layout.

Memory IC Selection Notes

Select this component when a 64-Kbit capacity is required with low-power CMOS technology. It is suitable for applications needing flexible write protection levels and compatibility with standard SPI interfaces. Consider the 1.8V minimum operating voltage for low-voltage system designs.

Memory IC Part Context

This part belongs to the 25AA640A/25LC640A family of 64-Kbit Serial EEPROMs. The 'AA' designation typically denotes a 1.8V to 5.5V operating range, distinguishing it from the 'LC' variant which starts at 2.5V. The 'T' suffix indicates tape and reel packaging, while 'ST' specifies the TSSOP package.

Memory IC Replacement Considerations

The 25LC640A series serves as a functional alternative but requires a minimum supply voltage of 2.5V instead of 1.8V. Verify voltage compatibility before substitution. Other package variants like MSOP or SOIC may be interchangeable if pinout and thermal requirements are met.