The four 24-bit sigma-delta converters are the headline differentiator. In a three-phase energy meter, each phase voltage and current pair needs a dedicated ADC channel; this part covers that with one converter per phase plus a fourth for neutral or reference. That integration removes the need for an external multi-channel ADC or a front-end analog multiplexer, shrinking the BOM and board area. The 32 KB RAM provides enough working space for the accumulated energy registers and communication buffers without external SRAM. The 512 KB Flash holds the application code, calibration constants, and a logging buffer for several months of interval data.
Package and temperature grade for the environment
The MSP430F67491IPEU is supplied in a 128-pin LQFP package with a 20x14 mm body. The surface-mount footprint is standard for this pin count; the 0.5 mm pitch requires careful solder-paste stencil design for reliable reflow.