Elapsed Time Counter Module

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The DS1603 Elapsed Time Counter provides multiple-purpose, low-cost, nonvolatile timekeeping with two 32-bit counters. One counter constantly maintains real time by counting seconds, whether powered from system or from backup supplies. The other counts only when system power is active, which is useful for monitoring operational on-time for warranty or billing purposes related to equipment use. Under software control, this counter can also count signals to track external real-time events. Both counters output binary data that can be read in standard clock and calendar format using a software algorithm. Read/write communication is transmitted over a 3-wire serial port.

The DS1603 module incorporates a 32.768kHz crystal and backup battery. Installed in a processor-controlled system, the DS1603 combines timekeeping and counting functions at extremely low cost with minimal current consumption.

Key Features

  • Two 32-bit counters track time in seconds for >125 years
  • One counter tracks real time on system or battery power while battery input >2.5V
  • One counter tracks elapsed time under system power and holds the count under battery power
  • Clear function resets a selected counter to zero
  • Read/write serial port affords low pin count
  • Maximum current drain <1µA with serial port disabled
  • 1-byte protocol defines read/write, counter address and software clear function
  • Operating temperature range: 0°C to 70°C
Request Reliability Report for: DS1603 
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Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

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