Abstract: An analogue to digital multi-slope converter has an integrator 10 to which an analogue input signal 30 is continuously applied. A reference voltage 36, 37 is superimposed onto the integrator input 30 in pulse form, being switched on and off according to a predetermined program controlled by a clock and modified by a comparator 11 such that reference voltage pulses occur in pairs of opposite polarity. The sequence of pulses is applied in such a manner that the final pulse of a sequence causes the integrator output to move towards a comparator 11 reference level, the reference voltage then being maintained until the reference level is reached after which a new cycle is started.