What this part is and where it lands
The Texas Instruments MSP430F6777AIPZR is a 16-bit microcontroller from the MSP430F6xx family, built around the CPUXV2 core running at 25 MHz. It carries 256 KB of Flash program memory and 32 KB of RAM — enough for three-phase energy metering firmware plus Modbus or DLMS communication stacks. The standout feature is the seven 24-bit sigma-delta ADCs on-chip, purpose-built for polyphase power measurement where you need simultaneous voltage and current sampling per phase. An additional 8-channel 10-bit SAR ADC handles auxiliary inputs like temperature or tamper detection. The 62 general-purpose I/O lines and peripheral set — including I²C, SPI, UART/USART, IrDA, and LINbus — let it double as the system controller, not just a metering front-end.
25 MHz — what it buys you in a metering design
At 25 MHz the CPUXV2 can execute a 16×16 multiply-accumulate in a single cycle, which matters when computing active, reactive, and apparent power across three phases every line cycle.
Package and temperature grade — the physical fit
Housed in a 100-pin LQFP (14×14 mm body), surface-mount only. The -40 to 85 °C industrial temperature range covers outdoor meter cabinets and factory-floor enclosures without active cooling.