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