Abstract: A periodically integrating analog-to-digital converter and a sensor device having such a converter. The analog-to-digital converter has a measured-value-to-pulse-amount converter, i.e., a sigma-delta converter of the first order that is reset to zero before each new period, and a digital counter for the number of feedback signals of known reference value in the measured-value-to-pulse-amount converter. This constitutes a rough measure of the input signal. The analog-to-digital converter also converts the residual value of the measured-value-to-pulse-amount converter at the end of the period to a digital value, and an adder which adds this value to the output signal from the digital counter, resulting in a more accurate measure of the input signal.