The Microchip Technology Inc. 25AA640A/25LC640A (25XX640A) is a 64-Kbit Serial Electrically Erasable PROM accessed via a simple SPI serial bus. It features low-power CMOS technology, a maximum clock frequency of 10 MHz, and includes data protection circuitry. Suitable for applications requiring non-volatile data storage in SPI-based systems, it offers endurance of 1,000,000 erase/write cycles and data retention exceeding 200 years. Available in multiple packages including DFN, MSOP, PDIP, SOIC, TDFN, and TSSOP, it caters to a wide range of design requirements.