Abstract: An analog-to-digital converter includes a delta sigma modulator (103) adapted to produce a stream of pulses (104) the density of which represents the amplitude of an analog input signal (VIN) coupled to an input of the delta sigma modulator. A decimation filter (105) is coupled to filter the stream of pulses and produce a digital word (106) representing the amplitude of the analog input signal. A serial interface circuit (109) is coupled to serially receive the bits of the output word and serially shift the bits of the digital word to a data terminal (110). A timing generator (17) produces timing signals to control operation of the delta sigma modulator and the decimation filter and generates a conversion done signal (21) indicative of completion of conversion of the analog input signal (VIN) into the digital word.