25LC640-I/P

Overview

The Microchip Technology 25LC640-I/P is a 64 Kbit (8192 x 8 bit) Serial Electrically Erasable PROM. It utilizes a standard SPI-compatible serial bus interface requiring SCK, SI, SO, and CS signals. The device supports a maximum clock frequency of 3 MHz at supply voltages between 4.5 V and 5.5 V. It operates within an industrial temperature range of -40 °C to +85 °C and is housed in an 8-pin PDIP package.

Feature Summary

• Supports block write protection for none, one-quarter, one-half, or all memory array segments
• Includes built-in power-on/off data protection circuitry with a write enable latch
• Features a hold pin to pause serial communication without resetting the sequence

Applications

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

Procurement Notes

Verify that the specific ordering suffix matches the required package type and voltage specifications. Confirm the device revision aligns with current design requirements, as datasheets indicate this series may be superseded by newer variants like the 25LC640A. Ensure compatibility with the target system's SPI timing constraints.

Selection Notes

Select this component when a non-volatile memory solution with hardware-level write protection is required. The 8-pin PDIP package facilitates through-hole prototyping and assembly. Verify that the operating voltage range of the host system falls within the specified limits for the desired clock speed.

Part Context

This part belongs to the 25XX640 family of serial EEPROMs manufactured by Microchip Technology. The 'I' designation indicates compliance with industrial temperature standards. The device provides reliable data retention exceeding 200 years and high electrostatic discharge protection ratings.

Replacement Considerations

Datasheet documentation explicitly recommends using the 25AA640A or 25LC640A devices instead of this older generation part for new designs.