The internal timebase of the device is provided by an internal oscillator that is trimmed to less than 0.5% tolerance at room temperature. The precision oscillator is the timing source for ADC conversions, as well as the time-count used for calculation of energy and charge. The digital filter response varies with conversion time; therefore, the precise clock ensures filter response and notch frequency consistency across temperature. On power up, the internal oscillator and ADC take roughly 300 µs to reach <1% error stability. Once the clock stabilizes, the ADC data output will be accurate to the electrical specifications provided in Section 6.