25LC640-I/SN

Overview

The Microchip Technology 25LC640-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 operates within a supply voltage range of 2.5V to 5.5V and supports a maximum clock frequency of 3 MHz at VCC levels between 4.5V and 5.5V. It features self-timed erase and write cycles with a maximum duration of 5 ms. The component is housed in an 8-lead Small Outline Integrated Circuit (SOIC) package designed for surface mount installation.

Feature Summary

• Supports sequential read operations with automatic address pointer incrementation
• Includes built-in hardware write protection via dedicated pin and status register control
• Features power-on data protection circuitry and a write enable latch mechanism

Applications

• Microcontroller system configuration storage
• Data logging applications requiring non-volatile memory retention
• Embedded systems storing calibration parameters or user settings

Procurement Notes

Verify the specific suffix 'I/SN' corresponds to the Industrial temperature range (-40°C to +85°C) and the 8-lead SOIC package format. Confirm that the source documentation explicitly lists this part number as available, noting that datasheets may recommend newer alternatives like the 25LC640A series for new designs.

Selection Notes

Select this component when a 64 Kbit capacity is required with SPI interface compatibility. Ensure the operating environment stays within the industrial temperature limits and that the supply voltage remains above 2.5V. Consider the 32-byte page write capability for efficient data handling during programming sequences.

Part Context

This device belongs to the 25XX640 family of serial EEPROMs manufactured by Microchip Technology. It shares functional similarities with the 25AA640 but differs in minimum operating voltage requirements. The family is designed for low-power applications and offers high reliability with significant ESD protection capabilities across all pins.

Replacement Considerations

Datasheet guidance indicates that the 25LC640A is recommended over the 25LC640 for new designs. Verify if the 'A' suffix variant maintains identical pinouts and electrical characteristics before substitution.