The DS1314S+ is a 3V non-volatile controller with lithium battery monitor in 16 pin WSOIC package. The non-volatile controller with battery monitor is a CMOS circuit which solves the application problem of converting CMOS RAM into non-volatile memory. Incoming power is monitored for an out of tolerance condition. When such a condition is detected, chip enable is inhibited to accomplish write protection and the battery is switched on to supply the RAM with uninterrupted power. Special circuitry uses a low-leakage CMOS process which affords precise voltage detection at extremely low battery consumption.