25LC640-E/SN

Overview

The Microchip Technology 25LC640-E/SN is a 64 Kbit (8192 x 8 bit) Serial Electrically Erasable PROM. It features an SPI-compatible serial bus interface with a maximum clock frequency of 2 MHz at VCC = 2.5V to 5.5V. The device operates within a supply voltage range of 2.5V to 5.5V and supports industrial temperature ranges from -40°C to +85°C. It utilizes low-power CMOS technology, offering typical standby current of 500 nA and read current of 500 µA. The memory organization allows for sequential reads and page writes up to 32 bytes.

Feature Summary

• Supports self-timed erase and write cycles with a maximum cycle time of 5 ms.
• Includes built-in power on/off data protection circuitry and a write enable latch.
• Provides block write protection capabilities allowing none, 1/4, 1/2, or all of the array to be protected.
• Features a Hold pin that suspends transmission during serial sequences without resetting the sequence.

Applications

• Data storage in microcontroller systems via SPI port
• Configuration parameter retention
• Calibration data logging

Procurement Notes

Verify the specific suffix 'E' against official documentation, as standard datasheets typically list Industrial ('I') and Automotive ('E') temperature grades. Confirm the SOIC package type matches the required footprint. Ensure the component meets RoHS compliance standards if applicable to the target assembly process.

Selection Notes

Select this component for applications requiring non-volatile storage accessible via standard SPI interfaces. Consider the 2 MHz clock speed limit at lower voltages when designing high-speed communication loops. Verify that the 8-pin SOIC package dimensions fit the available PCB space and that the operating voltage aligns with the system's power rails.

Part Context

This part belongs to the 25xx640 family of serial EEPROMs manufactured by Microchip Technology. It shares architectural similarities with the 25AA640 but differs in supply voltage requirements. The datasheet notes that this specific generation is not recommended for new designs, suggesting the use of updated variants like the 25LC640A.

Replacement Considerations

Microchip recommends using the 25LC640A series as a replacement for new designs. Other compatible parts within the same family include the 25LC640T-I/SN and 25LC640X-I/ST, which offer similar specifications with different packaging options.