8.2.2.1 Design Requirements

For best performance, an RC low-pass filter can be used in front of the AMC1100. Further improvement can be achieved by filtering the output signal of the device. In both cases, the values of the resistors and the capacitors must be tailored to the bandwidth requirements of the system.

The analog output of the device is converted to the digital domain using the on-chip analog-to-digital converters (ADCs) of a suitable metrology microcontroller. The architecture of the MSP430F471x7 family of ultra-low power microcontrollers is tailored for this kind of applications. The MSP430F471x7 offers up to seven ADCs for simultaneous sampling: six of which are used for the three phase currents and voltages whereas the seventh channel can be used for additional voltage sensing of the neutral line for applications that require anti-tampering measures.