I²C, 32-Bit Binary Counter Watchdog RTC with Trickle Charger and Reset Input/Output

The DS1374 is a 32-bit binary counter designed to continuously count time in seconds. An additional counter generates a periodic alarm or serves as a watchdog timer. If disabled, this counter can be used as 3 bytes of nonvolatile (NV) RAM. Separate output pins are provided for an interrupt and a square wave at one of four selectable frequencies. A precision temperature-compensated reference and comparator circuit monitor the status of VCC to detect power failures, provide a reset output, and automatically switch to the backup supply when necessary.

Additionally, the reset pin is monitored as a pushbutton input for externally generating a reset. The device is programmed serially through an I²C serial interface.

Applications

* Medical Equipment * Point-of-Sale Equipment * Portable Instrumentation * Telecommunications

* 32-Bit Binary Counter

* Second Binary Counter Provides Time-of-Day Alarm, Watchdog Timer, or NV RAM

* Separate Square-Wave and Interrupt Output Pins

* I²C Serial Interface

* Automatic Power-Fail Detect and Switch Circuitry

* Single-Pin Pushbutton Reset Input/Open-Drain Reset Output

* Low-Voltage Operation

* Trickle-Charge Capability

* -40°C to +85°C Operating Temperature Range

* 10-Pin µSOP, 16-Pin SO

* Available in a Surface-Mount Package with an Integrated Crystal (DS1374C)