In summary, many types of military, avionics, and industrial equipment are required to record and alarm for the elapsed time of use or events, such as power cycles for warranty period tracking, preventative maintenance, or calibration scheduling. Three possible solutions are crystal-based real time clocks, microcontrollers, and all-silicon RC oscillators. Each has its advantages over the other, but the key benefit to the RC oscillators is that it does not require an external crystal or battery, thus creating a more robust design in environments with high shock, vibration, dust, humidity, etc. Two RC oscillator products from Analog Devices have been introduced, the DS1682 and DS1683, each tailored for specific event and elapsed time recording and alarming applications.