MSP430 audio sampling

Analog measurement

Measurements taken by the ADC are recorded as a fraction of a reference voltage. The "bits" used by the ADC to represent the reading determine the smallest change measurable by the ADC -- and the denominator of the fraction. In our case, the circuit is 3.3 volts - using this as a voltage reference means that a reading of 50% from the ADC would equal ~1.65 volts. The diagram demonstrates how reference voltage and resolution effect the measurements taken by the ADC.