25AA640-I/P

Memory IC Overview

The Microchip Technology 25AA640-I/P is a 64 Kbit (8192 x 8 bit) Serial Electrically Erasable PROM. It utilizes an SPI-compatible serial bus with SCK, SI, SO, and CS signals for communication. The device supports a HOLD pin to pause transmission without resetting the sequence. Operating voltage ranges from 1.8V to 5.5V. Maximum clock frequency is 1 MHz across the full voltage range. Industrial temperature range is -40°C to +85°C. Endurance is 1M cycles with data retention exceeding 200 years.

Memory IC Feature Summary

• Supports sequential read operations with automatic address pointer incrementation.
• Includes built-in write protection via power-on/off circuitry and a dedicated write-protect pin.
• Features block write protection allowing selection of none, one-quarter, one-half, or all array segments.

Memory IC Applications

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

Memory IC Procurement Notes

Verify the specific suffix 'I' confirms the industrial temperature range (-40°C to +85°C). Confirm the '/P' designation indicates the 8-pin PDIP package type. Ensure the base part number matches the legacy 25AA640 series rather than the newer A-series variants if strict compatibility is required.

Memory IC Selection Notes

Select this component when low-power CMOS technology is required for battery-operated applications. The 1.8V minimum supply voltage allows operation in low-voltage systems. The 32-byte page size facilitates efficient data writing compared to byte-only programming methods.

Memory IC Part Context

This device belongs to the 25XX640 family of serial EEPROMs manufactured by Microchip Technology. It shares architectural similarities with the 25LC640 but differs in operating voltage specifications. The datasheet notes that this specific generation is not recommended for new designs, suggesting consideration of updated alternatives.

Memory IC Replacement Considerations

Datasheet explicitly recommends using the 25AA640A or 25LC640A instead of this legacy part for new designs. Verify electrical compatibility before substituting with other 64Kb SPI EEPROMs.