X22C12P

256 x 4-Bit Non-Volatile Static RAM (NOVRAM) chip manufactured by Xicor Inc. This highly unique hybrid memory component combines a standard high-speed 1024-bit volatile Static RAM array overlayed bit-for-bit with a non-volatile Electrically Erasable PROM (EEPROM) mirror inside an 18-pin package. It functions by operating as a standard fast-access SRAM during normal processing routines, but instantly copies its entire 4-bit parallel memory matrix into the non-volatile EEPROM backup layer upon receiving a single hardware save command, preserving critical parameters when main system power cuts out. It was heavily implemented to store system boot parameters, device configuration scripts, calibration metrics, and encryption keys inside legacy network adapter cards, military-grade transceivers, and automated industrial PLC cabinets. (Industry Equals: Xicor X22C12P, Xicor X22C12, Intersil X22C12P, Catalyst X22C12, AMD X22C12, SGS-Thomson X22C12).