The DS1218 Nonvolatile Controller Chip supplies circuitry required to render standard CMOS RAM nonvolatile. Vcc is monitored using a precise comparator that detects power-fail and inhibits chip-enable holding a write-protect status until power supplies return to nominal levels. The DS1218 switches active power supplies between Vcc and a battery source, whichever is greater. The switch has a voltage drop of less than 0.2V.
주요기능
Controller circuitry with monitoring and logic functions to make CMOS RAM nonvolatile
Monitors Vcc and write-protects when out of tolerance