Microchip 25LC040-I/SN is a 4 Kbit serial Electrically Erasable PROM. The memory is accessed via a simple Serial Peripheral Interface (SPI) compatible serial bus. The bus signals required are a clock input (SCK) plus separate data in (SI) and data out (SO) lines. Access to the device is controlled through a Chip Select (CS) input. Communication to the device can be paused via the hold pin (HOLD).

Low-power CMOS technology: Write current: 3 mA, typical, Read current: 500 μA, typical, Standby current: 500 nA, typical
512 x 8-bit organization
16 byte page
Write cycle time: 5 ms max.
Self-timed Erase and Write cycles
Block write protection: Protect none, 1/4, 1/2 or all of array
Built-in write protection: Power on/off data protection circuitry, Write enable latch, Write-protect pin
Sequential read
Temperature ranges supported: Industrial (I): -40°C to +85°C, Automotive (E) (25C040): -40°C to +125°C