25AA256-E/SN

Memory IC Overview

The Microchip Technology 25AA256-E/SN is a 256 Kbit Serial Electrically Erasable PROM featuring a 32,768 x 8-bit organization. It utilizes an SPI-compatible serial bus with a maximum clock frequency of 10 MHz. The device operates within a supply voltage range of 1.8 V to 5.5 V and supports extended industrial temperature ranges from -40°C to +125°C. It is housed in an 8-lead SOIC package.

Memory IC Feature Summary

• Supports block write protection for none, one-quarter, one-half, or all array segments via status register configuration.
• Includes built-in power-on/off data protection circuitry and a dedicated write-protect pin.
• Features a hold input that allows pausing serial communication without resetting the sequence.

Memory IC Applications

• Data logging systems requiring non-volatile storage
• Configuration parameter storage in embedded controllers
• Calibration value retention in industrial sensors

Memory IC Procurement Notes

Verify the specific suffix 'E' confirms the extended temperature rating (-40°C to +125°C) and 'SN' indicates the narrow SOIC package. Confirm RoHS compliance status as required by your assembly specifications. Ensure the ordering quantity matches the manufacturer's standard packaging constraints.

Memory IC Selection Notes

Select this component when low-voltage operation down to 1.8 V is required alongside high-speed SPI access. The extended temperature grade suits harsh environments where standard industrial parts may fail. Compare against the 25LC256 variant if a higher minimum voltage threshold is acceptable for the design.

Memory IC Part Context

This EEPROM belongs to the 25XX256 family, which shares identical pinouts and instruction sets. The 25AA256 series specifically targets applications needing lower voltage operation compared to the 25LC256 series. Both variants utilize the same 8-pin packages including SOIC, TSSOP, and DFN options.

Memory IC Replacement Considerations

The 25LC256-E/SN serves as a direct functional substitute, differing primarily in its minimum operating voltage requirement of 2.5 V rather than 1.8 V. Verify voltage compatibility before swapping these components in existing designs.

Memory IC FAQ

How does the HOLD pin function during active communication?

The HOLD pin suspends serial transmission when pulled low while SCK is low. Transitions on SI, SCK, and SO are ignored until HOLD returns high, allowing the host to service interrupts without restarting the sequence.

What happens if a page write crosses a physical boundary?

If a page write command attempts to cross a physical page boundary, the data wraps around to the beginning of the current page instead of writing to the next page. Application software must prevent this occurrence.