25AA040XT/ST

Memory IC Overview

The Microchip Technology 25AA040XT/ST is a 4 Kbit (512 x 8) serial Electrically Erasable PROM. It operates within a supply voltage range of 1.8V to 5.5V and supports a maximum clock frequency of 1 MHz. The device utilizes an SPI-compatible interface with SCK, SI, SO, CS, HOLD, and WP pins. It features industrial temperature support (-40°C to +85°C) and is housed in an 8-lead TSSOP package.

Memory IC Feature Summary

• Low-power CMOS technology with typical standby current of 500 nA
• Hardware write protection via dedicated WP pin and software block protection
• Self-timed erase and write cycles with internal write enable latch
• Communication pause capability via HOLD pin without sequence reset

Memory IC Applications

• Microcontroller data storage for configuration parameters
• Non-volatile memory for system calibration values
• Industrial control systems requiring low power consumption
• Automotive electronics supporting extended temperature ranges

Memory IC Procurement Notes

Verify the specific suffix 'XT' indicates tape and reel packaging with an alternate pinout configuration for the TSSOP package. Confirm the device meets the required Industrial temperature range specifications. Ensure compatibility with the host controller's SPI voltage levels and clock speed limitations before integration into the design.

Memory IC Selection Notes

Select this component when a wide 1.8V to 5.5V operating voltage range is required. It is suitable for applications needing hardware write protection and sequential read capabilities. Consider the 16-byte page write restriction and the necessity of managing the write enable latch state for reliable data integrity during system operation.

Memory IC Part Context

This part belongs to the 25XX040 family of 4 Kbit Serial EEPROMs from Microchip Technology. It shares functional similarities with the 25LC040 and 25C040 variants but differs in minimum operating voltage and maximum clock frequency specifications. The XT suffix specifically denotes tape and reel packaging with an alternative pin arrangement for the TSSOP form factor.

Memory IC Replacement Considerations

The datasheet explicitly states that the 25AA040/25LC040/25C040 series is not recommended for new designs. Engineers should consider upgrading to the 25AA040A or 25LC040A devices as direct replacements for new projects.