Noise shaping and oversampling is accomplished in the sigma-delta modulator. This is a simple first-order single-bit modulator, and the output is a 1-bit stream of data. Because of feedback, the signal at B must (on the average) equal VIN. This ADC is inherently linear and monotonic because of the 1-bit ADC and 1-bit DAC. If VIN is zero (midscale), there are an equal number of "1"s and "0"s in the output data stream. The DC value of the input is equal to the ratio of the "1"s in the output stream to the total number of samples in the same interval.