DS1374

Features:

 32-Bit Binary Counter
Second Binary Counter Provides Time-of-Day
      Alarm, Watchdog Timer, or NV RAM
Separate Square-Wave and Interrupt Output Pins
I ²C 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 SOP, 16-Pin SO
Available in a Surface-Mount Package with an
     Integrated Crystal (DS1374C)
Underwriters Laboratory (UL) Recognized


Application

Portable Instruments
Point-of-Sale Equipment
Medical Equipment
Telecommunications


Pinout




Specifications

Voltage Range on VCC Pin Relative to Ground.....-0.3V to +6.0V
Voltage Range on SDA, SCL, and WDS
Relative to Ground....................................-0.3V to VCC + 0.3V
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range.............................-55°C to +125°C
Soldering Temperature Range........................See the Handling,
PC Board Layout, and Assembly section.

Description

The DS1374 is a 32-bit binary counter designed to continuously count time in seconds. An additional counter gen-
erates a periodic alarm or serves as a watchdog timer. If disabled, this counter DS1374 can be used as 3 bytes of non-
volatile (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 DS1374 is pro-
grammed serially through an I ² C(TM) serial interface.