Single-ended measurements typically have one input connected to a fixed potential (ground or dc voltage) and the other input is the signal. Usually, the fixed connection is the negative input. The positive input is the signal and is driven above and below the negative input, as depicted in Figure 10-1. This is an example of a bipolar signal because the positive input can swing above and below the negative input. Unipolar signals are those where the positive signal is equal to or greater than the negative signal. The single-ended signal plus the level-shift voltage must be within the ADC specified operating range. In single supply configurations (5 V), the level-shift voltage is usually 2.5 V. This type of input configuration is shown in Figure 10-2. For bipolar power supplies (±2.5 V), the negative voltage can be grounded. This type of input is shown in Figure 10-3.