25LC640T-I/SN

Overview

The Microchip Technology 25LC640T-I/SN is a 64 Kbit (8192 x 8 bit) Serial Electrically Erasable PROM. It utilizes a standard SPI-compatible serial bus for communication, requiring SCK, SI, SO, and CS signals. The device supports a maximum clock frequency of 2 MHz at supply voltages between 2.5V and 5.5V. It features low-power CMOS technology with typical standby current of 500 nA and read current of 500 μA. The component operates within an industrial temperature range of -40°C to +85°C and is housed in an 8-pin SOIC package.

Feature Summary

• Supports sequential reading and page write operations up to 32 bytes per cycle.
• Includes built-in hardware write protection via the WP pin and software block protection.
• Features self-timed erase and write cycles initiated by the Chip Select signal.
• Provides data retention exceeding 200 years and ESD protection greater than 4000V.

Applications

• Data storage for microcontroller systems
• Configuration parameter storage
• Calibration data retention

Procurement Notes

Verify that the specific suffix 'T' corresponds to tape-and-reel packaging as indicated by distributor listings. Confirm the 'I' designation matches the required industrial temperature range (-40°C to +85°C). Ensure the voltage supply aligns with the 2.5V to 5.5V operational limits specified for the 2 MHz clock frequency. Cross-reference the datasheet revision DS21223H for accurate electrical characteristics.

Selection Notes

Select this component when a non-volatile memory solution with SPI interface compatibility is required for industrial environments. It is suitable for applications needing moderate data density with low power consumption during standby. Consider the 32-byte page write capability for efficient data updates. Verify that the system voltage remains within the 2.5V to 5.5V range to ensure reliable operation at the specified clock speeds.

Part Context

This part belongs to the 25LC640 series of serial EEPROMs from Microchip Technology. It shares functional similarities with the 25AA640 but differs in operating voltage ranges. The device is designed for direct interfacing with popular microcontroller families. It serves as a cost-effective solution for storing small amounts of persistent data in embedded systems.

Replacement Considerations

The datasheet notes that the 25LC640 is not recommended for new designs and suggests using the 25LC640A instead. The 25LC640A offers improved specifications and is the current recommended alternative within the same product family.