Above is an example of an RMS-to-DC application. High voltage power metering is important in applications like power meters and electric vehicles. In this circuit, the 330 volt peak-to-peak signals are fed to the AD628 high voltage difference amplifier for attenuation. The attenuated signals are fed to the ± 15 volt powered AD8436. Thus, accurate results can be obtained in milliseconds over a wide temperature range. The tested waveforms of 330 volts peak-to-peak input, 13.2 volts peak-to-peak attenuated, and RMS output signals are provided on this slide. The AD8436 was selected because of its wide dynamic range, faster settling time, high input impedance, and 36 volt power supply range. What’s more is that because of its high level of integration, the AD8436 is easy to use and consumes minimal PCB area. Additionally, this circuit can easily be extended to a multiplexed 3-phase solution if needed.