25AA040AXT-I/ST

Memory IC Overview

The Microchip Technology 25AA040AXT-I/ST is a 4 Kbit (512 x 8) Serial Electrically Erasable Programmable Read-Only Memory (EEPROM). It operates within a supply voltage range of 1.8V to 5.5V and supports a maximum clock frequency of 10 MHz via an SPI-compatible serial bus. The device features a 16-byte page write capability, self-timed erase/write cycles with a maximum duration of 5 ms, and industrial temperature support from -40°C to +85°C. It is housed in an 8-lead X-Rotated TSSOP package.

Memory IC Feature Summary

• Supports low-power CMOS technology with typical standby current of 5 µA at 5.5V.
• Includes built-in write protection mechanisms such as power-on/off data protection circuitry and a dedicated write-protect pin.
• Features block write protection allowing selection of none, 1/4, 1/2, or all array segments.

Memory IC Applications

• Microcontroller system data storage
• Configuration parameter retention
• Calibration value storage

Memory IC Procurement Notes

Verify the specific ordering suffix 'XT' against official documentation to confirm the X-Rotated TSSOP package type and tape-and-reel delivery format. Ensure the 'I' designation matches the required industrial temperature range of -40°C to +85°C for your application environment.

Memory IC Selection Notes

Select this component when a 4 Kbit EEPROM is required with a wide 1.8V to 5.5V operating voltage range. It is suitable for designs needing high-speed SPI communication up to 10 MHz and compact surface-mount packaging options like the X-Rotated TSSOP.

Memory IC Part Context

This part belongs to the 25XX040A family of 4 Kbit SPI Serial EEPROMs manufactured by Microchip Technology. The family includes variants with different voltage ranges and packages, sharing common functional specifications and instruction sets.

Memory IC Replacement Considerations

Compatible substitutes include other 25AA040A variants with different packages (e.g., SOIC, MSOP) or the 25LC040A series, provided the minimum supply voltage requirements align with the system design.

Memory IC FAQ

How does the HOLD pin function during operation?

The HOLD pin allows the user to pause serial communication without resetting the sequence. Transitions on SI, SCK, and SO are ignored while held low, and communication resumes when the pin is brought high while SCK is low.

What is the maximum page size for write operations?

The device supports a page write mode of up to 16 bytes. All bytes in a single write operation must reside within the same physical page boundary.