The TIDA-010197 demonstrates two different approaches for the analog front end (AFE). The first option is to use an external ADC paired with the MSP430FR5969-SP. The second option is to use the integrated ADC in the MSP430FR5969-SP allowing for a smaller solution size.

The first option uses the 12-bit SAR ADC, ADC128S102QML-SP, which offers a high accuracy and speeds with a FSR of 5 V. The second option uses the integrated ADC, which is a 12-bit SAR ADC FSR of 2.5 V.

Selecting a low-power 12-bit SAR ADC like the ADC128S102QML-SP helps to achieve the resolutions and speed needed to meet design goals. Both the external and integrated solutions have the same signal conditioning architecture leading up to the ADC. This includes the components and circuitry associated with the voltage and current measurements, voltage range scaling, current-voltage conversion, signal conditioning, and reference voltage generation. The AFE outputs the resulting voltage and current signals for input to the buffer, gain stage, and ADC, which is interfaced with the MSP430FR5969-SP through an SPI.