25AA640A-I/ST

Memory IC Overview

The Microchip Technology 25AA640A-I/ST is a 64-Kbit (8192 x 8-bit) Serial Electrically Erasable PROM accessed via an SPI-compatible bus. It operates within a supply voltage range of 1.8V to 5.5V and supports a maximum clock frequency of 10 MHz at higher voltages. The device features a 32-byte page size, self-timed erase/write cycles with a maximum duration of 5 ms, and industrial temperature operation from -40°C to +85°C. It utilizes Low-Power CMOS technology with standby current as low as 1 µA.

Memory IC Feature Summary

• Supports serial communication through standard SPI signals including SCK, SI, SO, CS, HOLD, and WP pins.
• Includes hardware write protection controlled by the WP pin and STATUS register bits for data security.
• Features built-in power-on/off data protection circuitry and a write enable latch mechanism.
• Provides block write protection allowing selective protection of none, one-quarter, one-half, or all memory array segments.

Memory IC Applications

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

Memory IC Procurement Notes

Verify that the ordering suffix matches the required package type and temperature grade. Confirm the specific revision level against the manufacturer datasheet DS20001830G. Ensure compatibility with system voltage levels and SPI timing requirements before integration.

Memory IC Selection Notes

Select this component when a 64-Kbit non-volatile memory solution is required with SPI interface compatibility. Consider the 1.8V minimum operating voltage for low-power applications. Verify that the industrial temperature range meets environmental specifications.

Memory IC Part Context

This part belongs to the 25XX640A family of 64-Kbit Serial EEPROMs manufactured by Microchip Technology. The 'I' suffix indicates the Industrial temperature range variant (-40°C to +85°C). The 'ST' suffix denotes the 8-Lead TSSOP package configuration.

Memory IC Replacement Considerations

The 25LC640A is a functionally similar device within the same family but requires a minimum supply voltage of 2.5V instead of 1.8V. Other package variants such as MSOP or SOIC share identical electrical characteristics and pinouts.