DESCRIPTION
The DS1210 Nonvolatile Controller Chip is a CMOS circuit which solves the application problem of converting CMOS RAM into nonvolatile 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. The 8-pin DIP package keeps PC board real estate requirements to a minimum. By combining the DS1210 Nonvolatile Controller Chip with a CMOS memory and batteries, nonvolatile RAM operation can be achieved.

FEATURES
■ Converts CMOS RAMs into Nonvolatile
   Memories
■ Unconditionally Write Protects when VCC is
   Out-of-Tolerance
■ Automatically Switches to Battery when
   Power-Fail Occurs
■ Space-Saving 8-Pin DIP
■ Consumes <100nA of Battery Current
■ Tests Battery Condition on Power up
■ Provides for Redundant Batteries
■ Optional 5% or 10% Power-Fail Detection
■ Low Forward Voltage Drop on the VCC
   Switch
■ Optional 16-Pin SOIC Surface Mount
   Package
■ Optional Industrial (N) Temperature Range of
   -40°C to +85°C