The MSP430F67751AIPZR: The 25 MHz core runs the metrology calculations across three phases while maintaining real-time communication over SPI or UART.
7x24-bit sigma-delta ADC — the differentiator
The seven independent 24-bit sigma-delta ADCs are the headline feature of this device. They allow simultaneous sampling of three voltage and three current channels (for three-phase four-wire metering) plus a neutral current or reference channel, all with 24-bit resolution. The converters include a programmable gain amplifier and digital filter, so the MCU can directly interface with current transformers or shunt resistors without an external signal-conditioning stage.
The 100-LQFP package (14x14 mm body) provides 62 general-purpose I/O pins.