25LC640AT-E/SN

Overview

The Microchip Technology 25LC640AT-E/SN is a 64-Kbit (8192 x 8-bit) Serial Electrically Erasable PROM featuring an SPI-compatible interface. It operates within a voltage range of 2.5V to 5.5V and supports a maximum clock frequency of 10 MHz at VCC ≥ 4.5V. The device utilizes low-power CMOS technology with standby current as low as 1 µA. It offers high reliability, including 1,000,000 erase/write cycles and data retention exceeding 200 years. The component is housed in an 8-lead SOIC package and is qualified for extended industrial temperature ranges from -40°C to +125°C.

Feature Summary

• Supports serial communication via a standard four-wire SPI bus with separate data input and output lines.
• Includes hardware write protection mechanisms such as a dedicated Write-Protect pin and software-configurable block protection bits.
• Features a Hold pin that allows the host to pause serial transmission without resetting the internal address pointer.
• Integrates power-on/off data protection circuitry and a write enable latch to prevent inadvertent writes.

Applications

• Data logging systems requiring non-volatile storage for sensor readings or event timestamps.
• Configuration storage for microcontrollers and embedded processors.
• Calibration data retention in industrial instrumentation.
• Parameter storage in consumer electronics devices.

Procurement Notes

Verify the specific suffix 'E' indicates the Extended temperature range (-40°C to +125°C) rather than Industrial. Confirm the 'SN' suffix corresponds to the 8-lead SOIC package. Ensure the datasheet version matches the required revision for timing characteristics. Check RoHS compliance status if environmental regulations apply to the target assembly process.

Selection Notes

Select this part when an SPI interface is preferred over I2C for simpler protocol implementation. Choose the Extended temperature grade if the application environment exceeds standard industrial limits. Consider the page write size of 32 bytes for buffer management efficiency. Verify voltage compatibility with the system's logic levels, noting the minimum operating voltage is 2.5V.

Part Context

This component belongs to the 25LC640A family of 64-Kbit serial EEPROMs manufactured by Microchip Technology. It shares functional similarities with the 25AA640A but differs in supply voltage requirements. The family supports multiple package options including MSOP, TSSOP, and DFN variants.

Replacement Considerations

25LC640A-I/SN