25LC256T-E/ST

Overview

The Microchip Technology 25LC256T-E/ST is a 256 Kbit (32K x 8) Serial Electrically Erasable PROM. It utilizes an SPI-compatible serial bus for communication, supporting clock frequencies up to 10 MHz. The device operates within a supply voltage range of 2.5 V to 5.5 V and features low-power CMOS technology with standby current as low as 1 µA. It offers high reliability with 1,000,000 erase/write cycles endurance and data retention exceeding 200 years. The component is housed in an 8-lead TSSOP package and supports extended industrial temperature ranges from -40°C to +125°C.

Feature Summary

• Supports block write protection allowing selective array segments to be protected against writes.
• Includes built-in power-on/off data protection circuitry and a write enable latch mechanism.
• Features a hold pin that allows pausing serial communication without resetting the sequence.

Applications

• Microcontroller systems requiring non-volatile storage for configuration parameters.
• Industrial sensor nodes needing reliable data logging capabilities.
• Embedded devices storing calibration constants or user settings.

Procurement Notes

Verify the specific suffix 'E' confirms the extended temperature rating (-40°C to +125°C). Confirm the 'ST' suffix corresponds to the 8-lead TSSOP package type required for your PCB layout. Ensure the datasheet revision matches the design requirements for timing characteristics. Check for RoHS compliance status if environmental regulations apply to the final assembly.

Selection Notes

Select this part when an SPI interface is preferred over parallel buses to save I/O pins. The 25LC256 is suitable for applications requiring moderate write endurance and long-term data retention. Consider the page size constraints for write operations, as writes must not cross physical page boundaries. Verify voltage compatibility with the host microcontroller's logic levels.

Part Context

This component belongs to the 25XX256 family of serial EEPROMs manufactured by Microchip Technology. It shares functional similarities with the 25AA256 but differs in operating voltage specifications. The family provides a standardized solution for small-scale non-volatile memory needs across various embedded platforms.

Replacement Considerations

Check for equivalent parts from other manufacturers offering compatible SPI interfaces and pinouts. Verify that any substitute meets the same voltage and temperature requirements. Ensure the replacement supports the necessary write endurance and data retention specifications for the application.