DESCRIPTION

The DS1314 Nonvolatile Controller with Battery Monitor is a CMOS circuit which solves the application problem of converting CMOS RAM into nonvolatile memory. Incoming power is monitored for an outof-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.

FEATURES

■ Converts CMOS SRAM into nonvolatile
memory
■ Unconditionally write-protects SRAM when
VCC is out of tolerance
■ Automatically switches to battery backup
supply when VCC power failure occurs
■ Monitors voltage of a lithium cell and
provides advanced warning of impending
battery failure
■ Signals low-battery condition on active low
Battery Warning output signal
■ Automatic VCC power-fail detection for 3.0V
or 3.3V power supplies
■ Space-saving 8-pin DIP and SOIC packages
■ Optional 16-pin SOIC and 20-pin TSSOP
versions reset processor when power failure
occurs and hold processor in reset during
system power-up
■ Industrial temperature range of -40°C to
+85°C