Parallel-Interface Elapsed Time Counter

Elapsed time counter offers automatic power-fail detect, 244 µs resolution, and maximum count of over 136 years

Image of Maxim Integrated's Parallel-Interface Elapsed Time CounterMaxim's DS1318 parallel-interface elapsed time counter (ETC) is a 44-bit counter that maintains the amount of time that the device operates from main and/or backup power or during an external event. The internal frequency of the counter clock is 4.096 kHz, which provides a 244 µs resolution and a maximum count of over 136 years. A built-in power-sense circuit detects power failures, automatically switches to the backup supply, and controls the timer. If an external event timer is desired, the control input EXT can control the counter operation. An open-drain output provides an interrupt, and a square-wave output provides a programmable square wave. The DS1318 is accessed through a byte-wide parallel interface, and operates over the industrial temperature range.

  • Byte-wide parallel interface
  • 44-bit binary counter provides timer with 244 µs resolution
  • Industrial temperature range: -40°C to +85°C
  • Automatic power-fail detect and switch circuitry selects power source from the primary power and the battery, and write-protects the internal registers
  • Internal power-fail circuit allows timer to provide primary or battery operation times
  • Interrupt output generated periodically or when the upper 32 bits of the counter match an alarm register
  • Square-wave output with 16 selectable frequencies from 32.768 kHz to 0.5 Hz
  • Timer can alternately provide an event timer of either an active-high or active-low pulse
  • +3.3 V operation
  • UL recognized


  • Industrial controls
  • Power metering
  • Servers

Parallel-Interface ETC

ImageManufacturer Part NumberDescriptionTypeFeaturesAvailable Quantity
DS1318E+ datasheet linkIC RTC ELAPSED CNT PAR 24-TSSOPDS1318E+IC RTC ELAPSED CNT PAR 24-TSSOPElapsed Time CounterAlarm, Square Wave Output624 - Immediate
DS1318E+ product page link
Published: 2012-10-16