Using 60Hz Power Line Frequency as an Accurate Real Time Clock Timebase Using 60Hz Power Line Frequency as an Accurate Real Time Clock Timebase Application Note August 3, 2007 AN1342.0 Introduction Circuit Description (See Figure 2) Real Time Clock (RTC) devices contain an oscillator and Input Clock Conversion normally require a crystal to operate with the required This application circuit uses a wall transformer for the AC accuracy. Crystal oscillators are a good solution in that they ……